913 terms

iGCSE Chemistry: Y10 End of Year - test myself

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Describe the arrangement and movement of the particles in a liquid
Particles are close together but irregular. The particles are free to move.
Describe the arrangement, movement and energy of the particles in a gas
Particles are far apart and there are no forces between them. Energy is high. The particles move quickly and freely.
Describe the arrangement, movement and energy of the particles in a solid
Particles are close together and regularly packed. Energy is low. The particles vibrate around a fixed point.
Describe the arrangement of particles in a gas
Particles are spaced far apart
Describe the arrangement of particles in a liquid
Particles are close together
Describe the arrangement of particles in a solid
Particles are close together
Describe the changes in arrangement, movement and energy of particles when a liquid cools to become a solid
Arrangement becomes more regular. Particles vibrates in a fixed position. Particles lose energy
Describe the changes in arrangement, movement and energy of particles when a liquid turns into a solid
The particles form a regular arrangement, they slow down and lose kinetic energy
Describe the energy of particles in a gas
Particles have a lot of kinetic energy
Describe the energy of particles in a liquid
Particles have a moderate amount of kinetic energy
Describe the energy of particles in a solid
Particles have a little kinetic energy
Describe the movement of particles in a gas
Particles are free to move and moving quickly
Describe the movement of particles in a liquid
Particles are free to move and moving moderately
Describe the movement of particles in a solid
Particles vibrate around fixed positions
Draw 3 particle diagrams to show the arrangement of particles in a solid, liquid and gas. Draw arrows between them and label boiling, condensing and freezing
X=boiling, Y=condensing, Z=freezing
What happens when something condenses?
Condensation is the change of state when a substance cools from gas to liquid
What happens when something evaporates?
Evaporation is the change of state when a substance heats up from liquid to gas
What happens when something freezes?
Freezing is the change of state when a substance cools from liquid to solid
What happens when something melts?
Melting is the change of state when a substance heats up from solid to liquid
Define the term Saturated Solution
When no more solute can dissolve in a solution
Define the term Solute
The substance that dissolves in a solvent, forming a solution
Define the term Solution
The mixture of a soluble solute and a solvent
Define the term Solvent
The liquid which dissolves a solute
(Triple only) Define the term Solubility
A measure of how much solute dissolves in a solvent (in g per 100g)
(Triple only) What is the unit of solubility?
g of solute per 100g of solvent
(Triple only) A graph shows the solubility of sodium chloride in water at 50°C is 34g/100g. At that temperature, what mass of sodium chloride will dissolve in 200g water?
68g
(Triple only) A graph shows the solubility of sodium chloride in water at 50°C is 34g/100g. At that temperature, what mass of sodium chloride will dissolve in 50g water?
17g
(Triple only) State 2 ways in which more solute could be dissolved in a saturated solution
Heat the solution. Add more solvent.
(Triple only) What observation would be made if a saturated solution is cooled?
Solid would come out of solution
Draw 4 diagrams to show the particles in i) element, ii) compound, iii) mixture, iv) diatomic element
How many different elements are there in Be(OH)₂ ?
3
What is meant by the term compound?
A compound is a substance that contains two or more elements chemically joined together
What is meant by the term element?
An element is a substance made of only one type of atom
What is meant by the term mixture?
Different substances in the same space, but not chemically combined.
A substance is found to melt at a single, fixed melting point. Is it likely to be a pure substance or a mixture of substances?
Pure
A substance is found to melt over a range of temperatures. Is it a pure substance or a mixture of substances?
Mixture
Describe how pure salt can be obtained from rock salt
1) Grind rock salt into a fine powder. 2) Add powder to hot water and stir to dissolve salt. 3) Filter mixture. Salt solution passes through the filter paper leaving behind the sand. 4) Boil filtrate to evaporate some of the water. 5) Leave saturated solution to cool so that crystals of salt form. 6) Filter cold mixture to separate the crystals from the remaining solution.
Draw a beaker
Draw a conical flask
Draw a diagram to show equipment used in simple distillation
Draw a funnel
Draw a mass balance
Draw a measuring cylinder
Draw a test/boiling tube
Draw a thermometer
Draw a tripod
Draw an evaporating basin
Draw the equipment used in fractional distillation in the lab
Explain how fractional distillation is used to separate a mixture of different liquids
The different liquids have different boiling points
For what is the process of filtration used?
To separate an insoluble solid from a liquid
For what is the process of fractional distillation used?
To separate a mixture of different liquids that have different boiling points
For what is the process of simple distillation used?
To separate a liquid from a solution
For what is the separation technique of crystallisation used?
To obtain a dissolved salt from a salt solution
For what is the separation technique of paper chromatography used?
To separate various dyes from a mixture of dissolved dyes
State the method used to extract the red dye from a sample of rose petals
dissolving
State the method used to obtain kerosene from crude oil
fractional distillation
State the method used to obtain red food dye from a mixture of food dyes
paper chromatography
State the method used to obtain sand from a mixture of sand and water
filtration
State the method used to obtain solid copper sulfate from aqueous copper sulfate
crystallisation
State the method used to obtain water from salt water
simple distillation
Explain how a chromatogram shows that different dyes are different from each other
Each dye has components which rise to a different height on the paper
In paper chromatography if several dyes rise up the paper, why might another dyes not rise?
The other dye is insoluble in the solvent being used
In chromatography, what are the minimum and maximum possible values for an Rf value?
Minimum=0. Maximum=1.
What is the formula for calculating an Rf value?
Distance the dye has travelled divided by distance the solvent front has travelled. Both measured from the baseline.
In a paper chromatography experiment using a flammable solvent, why might a lid be used? (2)
To prevent the solvent from evaporating, and to reduce the risk of the solvent catching fire
In paper chromatography, the paper is position so it touches the solvent, but why is the paper position so baseline onto which dyes are placed is above the solvent?
So the dyes don't simply dissolve into the solvent
In paper chromatography, why is the baseline drawn in pencil?
Pencil will not dissolve in the solvent, but if ink were used instead it might dissolve and interfere with the results of the chromatography.
What is meant by the term atom?
An atom is the smallest part of an element
What is meant by the term molecule?
A molecule is made of a fixed number of two or more atoms covalently bonded together
What is the total number of atoms in the formula Be(OH)₂ ?
5
What is meant by the term atom?
An atom is the smallest part of an element
Explain why atoms are neutral
The numbers of electrons and protons are equal
State the mass and charge of a neutron
Neutron: mass=1, charge =0
State the mass and charge of a proton
Proton: mass=1, charge=+1
State the mass and charge of an electron
Electron: mass=almost zero, charge=-1
State the particle that is found in the shells orbiting the nucleus
Electrons
State the particles that are found within the nucleus of an atom
Protons and neutrons
What are the three subatomic particles?
protons, neutrons and electrons
What are the two parts of an atom?
The nucleus and the electron shells
Which particle in an atom has a negative charge?
Electron
Which particle in an atom has a posiive charge?
proton
Which particle in an atom has the smallest mass?
Electron
How many neutrons in a typical atom of carbon?
6
How many neutrons in a typical atom of fluorine?
10
How many neutrons in a typical atom of hydrogen?
0
How many neutrons in a typical atom of magnesium?
12
How many neutrons in a typical atom of sulfur?
14
How many protons in a fluorine atom?
9
How many protons in a helium atom?
2
How many protons in a hydrogen atom?
1
How many protons in a phosphorus atom?
15
How many protons in a potassium atom?
19
How many protons in a silicon atom?
14
How many protons in a sodium atom?
11
In terms of mass and atomic number, what are isotopes?
Isotopes are atoms with the same atomic number but a different mass
In terms of subatomic particles, what are isotopes?
Isotopes are atoms with the same number of protons but with a different number of neutrons
Tritium, an isotope of hydrogen, has a mass number of 3. How many neutrons does an atom of tritium contain?
2
What are isotopes?
Isotopes are atoms of the same element (same number of protons) but with a different number of neutrons (different mass)
What is a mass number?
Mass number is the number of protons plus the number of neutrons in an atom
What is an atomic number?
The atomic number is the number of protons in an atom
What is meant by the term relative atomic mass, Aᵣ?
The average mass of an atom of an element, relative to 1/12th of the mass of an atom of carbon-12
What is the atomic number of a beryllium atom?
4
What is the atomic number of a boron atom?
5
What is the atomic number of a calcium atom?
20
What is the atomic number of a carbon atom?
6
What is the atomic number of a chlorine atom?
17
What is the atomic number of an argon atom?
18
What is the atomic number of an oxygen atom?
8
What is the relative atomic mass (Aᵣ) of a helium atom?
4
What is the relative atomic mass (Aᵣ) of a hydrogen atom?
1
What is the relative atomic mass (Aᵣ) of a potassium atom?
39
What is the relative atomic mass (Aᵣ) of a silicon atom?
28
What is the relative atomic mass (Aᵣ) of a sodium atom?
23
How many neutrons in a typical atom of carbon?
6
How many neutrons in a typical atom of fluorine?
10
How many neutrons in a typical atom of hydrogen?
0
How many neutrons in a typical atom of magnesium?
12
How many neutrons in a typical atom of sulfur?
14
How many protons in a fluorine atom?
9
How many protons in a helium atom?
2
How many protons in a hydrogen atom?
1
How many protons in a phosphorus atom?
15
How many protons in a potassium atom?
19
How many protons in a silicon atom?
14
How many protons in a sodium atom?
11
What is a mass number?
Mass number is the number of protons plus the number of neutrons in an atom
What is an atomic number?
The atomic number is the number of protons in an atom
What is meant by the term relative atomic mass, Aᵣ?
The average mass of an atom of an element, relative to 1/12th of the mass of an atom of carbon-12
What is the atomic number of a beryllium atom?
4
What is the atomic number of a boron atom?
5
What is the atomic number of a calcium atom?
20
What is the atomic number of a carbon atom?
6
What is the atomic number of a chlorine atom?
17
What is the atomic number of an argon atom?
18
What is the atomic number of an oxygen atom?
8
What is the relative atomic mass (Aᵣ) of a helium atom?
4
What is the relative atomic mass (Aᵣ) of a hydrogen atom?
1
What is the relative atomic mass (Aᵣ) of a potassium atom?
39
What is the relative atomic mass (Aᵣ) of a silicon atom?
28
What is the relative atomic mass (Aᵣ) of a sodium atom?
23
A sample of bromine contained the two isotopes in the following proportions: bromine-79 = 50.7% and bromine-81 = 49.3%. Calculate the relative atomic mass of bromine
((79x50.7)+(81x49.3))/100 = 79.99
A sample of carbon contained 98.90% carbon-12 and 1.10% carbon-13. Calculate the relative atomic mass of carbon
((12x98.90)+(13x1.10))/100 = 12.01
How are elements arranged in the periodic table?
in order by atomic number
On the Periodic table what is the meaning of the word Group?
A Group is a vertical column of similar elements
On the Periodic Table what is the meaning of the word Period?
A Period is a horizontal row of elements
How many electron shells do the elements in the second period have?
2
How many electron shells do the elements in the third period have?
3
How many electrons can the first shell hold?
2
How many electrons can the first, second and third shells hold?
First 2, second 8, third 8
How many electrons can the second shell hold?
8
How many electrons can the third shell hold?
8
How many electrons in a calcium atom?
20
How many electrons in a chlorine atom?
17
How many electrons in a helium atom?
2
How many electrons in a magnesium atom?
12
How many electrons in a nitrogen atom?
7
How many electrons in a sodium atom?
11
How many electrons in an argon atom?
18
How many electrons in the outer shell of group 1 elements?
1
How many electrons in the outer shell of group 2 elements?
2
How many electrons in the outer shell of group 3 elements?
3
How many electrons in the outer shell of group 4 elements?
4
How many electrons in the outer shell of group 5 elements?
5
How many electrons in the outer shell of group 6 elements?
6
How many electrons in the outer shell of group 7 elements?
7
Write the electronic configuration of argon
2,8,8
Write the electronic configuration of potassium
2,8,8,1
Are metal oxides acidic or basic?
Basic
Are non-metal oxides acidic or basic?
Acidic
If an element conducts electricity, is it typically a metal or a non-metal?
Metal
If an element doesn't conducts electricity, is it a metal or a non-metal?
Non-Metal
Which are described as acidic: metal oxides or non-metal oxides?
non-metal oxides
Which are described as basic: metal oxides or non-metal oxides?
metal oxides
If an element conducts electricity, is it typically a metal or a non-metal?
Metal
If an element doesn't conducts electricity, is it a metal or a non-metal?
Non-Metal
Where are metals found on the periodic table?
On the left, reaching across the middle
Where are non-metals found on the periodic table?
At the top right, plus hydrogen
Where are the transition metals on the Periodic Table?
In the middle
On the Periodic table what is the meaning of the word Group? What does that tell us about the electron configuration of the atom?
same number of electrons in the outer shell
On the Periodic Table what is the meaning of the word Period? What does that tell us about the electron configuration of the atom?
same number of electron shells
Explain, in terms of electrons, why isotopes have the same chemical properties
Isotopes have the same number of electrons
Why do elements in the same group of the periodic table have similar chemical properties?
Elements in the same group of the periodic table have the same number of electrons in their outer shell
Explain, in terms of the arrangement of electrons in its atoms, why neon is very unreactive
Neon has 8 electrons in the outer shell, so it is full. Therefore it does not easily gain or lose electrons
What are the elements in group 0 called?
Noble gases
What is special about the elements in group 0?
They are very unreactive (because they have full outer electron shells)
Which group of atoms has a full outer shell?
Group 0, the noble gases
Balance the equation for the reaction: ___ HCl(aq) + ___ MnO₂(s) → ___MnCl₂(aq) + ___H₂O(l) + ___ Cl₂(g)
4 HCl(aq) + MnO₂(s) → MnCl₂(aq) + 2H₂O(l) + Cl₂(g)
Balance the following equation: WO₃ + H₂ → W + H₂O
WO₃ + 3H₂ → W + 3H₂O
What do each of the following state symbols represent: (s), (l), (g), (aq)
(s) - solid. (l) - liquid. (g) - gas. (aq) - aqueous (in solution)
Calculate the relative formula mass(Mr) of a molecule of bromine (Br₂)
160
Calculate the relative formula mass(Mr) of aluminium nitrate (Al(NO₃)₃)
213
Calculate the relative formula mass(Mr) of aluminium oxide (Al₂O₃)
102
Calculate the relative formula mass(Mr) of ammonium nitrate (NH₄NO₃)
80
Calculate the relative formula mass(Mr) of calcium carbonate (CaCO₃)
100
Calculate the relative formula mass(Mr) of calcium hydroxide (Ca(OH)₂)
74
Calculate the relative formula mass(Mr) of carbon dioxide (CO₂)
44
Calculate the relative formula mass(Mr) of cobalt chloride crystals (CoCl₂.6H₂O)
238
Calculate the relative formula mass(Mr) of ethanol (C₂H₅OH)
46
Calculate the relative formula mass(Mr) of hydrated copper (II) sulfate (CuSO₄.5H₂O)
249.5
Calculate the relative formula mass(Mr) of propane (C₃H₈)
44
Calculate the relative formula mass(Mr) of zinc phosphide (Zn₃P₂)
257
What are the units for amount in Chemistry?
Moles
What is the meaning of the word mole in Chemistry?
A mole is the amount of a substance found in its relative formula mass in grams (e.g. in 24g of Magnesium)
Using relative atomic mass (Aᵣ) and relative formula mass (Mᵣ), complete the following expression: amount (in moles) =
mass / Mr
Using relative atomic mass (Aᵣ) and relative formula mass (Mᵣ), complete the following expression: mass =
amount (in moles) x Mr
Using relative atomic mass (Aᵣ) and relative formula mass (Mᵣ), complete the following expression: Mᵣ =
mass / amount (in moles)
What mass of calcium bromide will fully react with 71g of chlorine?
200g
What mass of carbon dioxide is produced when 24g of carbon undergoes completely combustion?
88g
In the thermal decomposition of calcium carbonate, we might expect 50g of calcium carbonate to produce 28g of calcium oxide. If instead only 24g of calcium oxide is produced, what is the yield?
86%
State the expression for calculating % yield.
% yield = (actual amount of products/theoretical amount of products) x100
1.170 g of CoCl₂.xH₂O gave a residue of 0.641 g on heating. Find x.
6
7.485 g of a hydrated copper(II) sulphate CuSO₄.xH₂O was heated producing 4.785g of anhydrous copper(II) sulphate. What is the formula of the hydrated salt?
CuSO₄.5H₂O
State the steps for calculating empirical formula
1) mass/Ar. 2) divide by the smallest. 3) Give the ratio has a whole number. 4) State final empirial formula
What is the empirical formula of an alcohol with the analysis; 52.2% C, 13.0% H and 34.8% O?
C₂H₆O
What is the formula of a compound in which 0.48 g of carbon combines with 0.08 g of hydrogen and 0.64 g of oxygen?
CH₂O
Work out the empirical formula of an oxide of chlorine contains 7.1 g of chlorine and 1.6 g of oxygen.
Cl₂O
State the steps for calculating empirical formula
1) mass/Ar. 2) divide by the smallest. 3) Give the ratio has a whole number. 4) State final empirial formula
Tungsten has the chemical symbol W. Suggest the chemical name of WO₃.
tungsten oxide
What is the empirical formula of an alcohol with the analysis; 52.2% C, 13.0% H and 34.8% O?
C₂H₆O
What is the formula of a compound in which 0.48 g of carbon combines with 0.08 g of hydrogen and 0.64 g of oxygen?
CH₂O
Work out the empirical formula of an oxide of chlorine contains 7.1 g of chlorine and 1.6 g of oxygen.
Cl₂O
What is meant by the term empirical formula?
A chemical formula that shows the simplest ratio of the numbers of atoms in a compound
What is meant by the term molecular formula?
A chemical formula that shows the actual numbers of the different types of atoms in a molecule
A compound that contained 24.24% Carbon. 4.04% Hydrogen and 71.72% Chlorine and has a relative molecular mass of 99. Calculate the empirical formula and the molecular formula.
Empirical formula is CH₂Cl. Molecular formula is also C₂H₄Cl₂
An oxide of nitrogen contains 26% nitrogen and 74% oxygen and has a relative molecular mass of 108. Find the empirical and molecular formulae for the oxide.
Empirical formula is N₂O₅. Molecular formula is also N₂O₅
(Triple only) A sample of hydrogen chloride gas has a volume of 48 dm³. What amount of hydrogen chloride is this?
2 moles
(Triple only) State the expression for calculating molar volume of a gas.
Molar volume = amount (in moles) x 24 dm³ or 24,000 cm³
(Triple only) What is the meaning of the term Molar Volume?
The volume of 1 mole of gas at r.t.p is called the molar volume (24dm³ or 24000cm³)
(Triple only) What volume does 0.5 moles of ethene gas occupy (at rtp)
12 dm³
(Triple only) What volume does 3 moles of carbon dioxide gas occupy (at rtp)?
72 dm³
To determine the formula of a metal oxide by combustion, magnesium is heated in a crucible. Why is a lid lifted from time to time?
To allow oxygen in so the magnesium fully reacts
To determine the formula of a metal oxide by combustion, magnesium is heated in a crucible. Why is a lid used?
To stop the escape of magnesium oxide smoke
To determine the formula of a metal oxide by combustion, magnesium is heated in a crucible. Why is the crucible is cooled, weighed, reheated, cooled, re-weighted, and so on?
By repeating till 2 consecutive masses are recorded, we know that the magnesium has all reacted
All the atoms in group 1 have 1 electron in their outer shell. What charge ions do they form?
+1
All the atoms in group 2 have 2 electron in their outer shell. What charge ions do they form?
+2
All the atoms in group 3 have 3 electron in their outer shell. What charge ions do they form?
+3
All the atoms in group 5 have 5 electron in their outer shell. What charge ions do they form?
-3
All the atoms in group 6 have 6 electron in their outer shell. What charge ions do they form?
-2
All the atoms in group 7 have 7 electron in their outer shell. What charge ions do they form?
-1
Describe, in terms of electrons, the formation of sodium chloride
An atom of sodium loses one electron. An atom of chlorine gains one electron
How many electrons in a calcium ion?
18
How many electrons in a carbon ion?
n/a
How many electrons in a chloride ion?
18
How many electrons in a fluoride ion?
10
How many electrons in a helium ion?
n/a
How many electrons in a hydrogen ion?
0
How many electrons in a lithium ion?
2
How many electrons in a magnesium ion?
10
How many electrons in a neon ion?
n/a
How many electrons in a nitride ion?
10
How many electrons in a phosphide ion?
18
How many electrons in a potassium ion?
18
How many electrons in a silicon ion?
n/a
How many electrons in a sodium ion?
10
How many electrons in a sulfide ion?
18
How many electrons in an aluminum ion?
10
How many electrons in an argon ion?
n/a
How many electrons in an oxide ion?
10
If an atom gains electrons what happens to its charge?
becomes more negative
If an atom loses electrons what happens to its charge?
becomes more positive
State the electron configuration of the aluminium ion
2,8
State the electron configuration of the calcium ion
2,8,8
State the electron configuration of the chloride ion
2,8,8
State the electron configuration of the fluoride ion
2,8
State the electron configuration of the magnesium ion
2,8
State the electron configuration of the nitride ion
2,8
State the electron configuration of the oxide ion
2,8
State the electron configuration of the phosphide ion
2,8,8
State the electron configuration of the potassium ion
2,8,8
State the electron configuration of the sodium ion
2,8
State the electron configuration of the sulfide ion
2,8,8
What is the formula of the aluminium ion?
Al³⁺
What is the formula of the beryllium ion?
Be²⁺
What is the formula of the bromide ion?
Br¹⁻
What is the formula of the calcium ion?
Ca²⁺
What is the formula of the chloride ion?
Cl¹⁻
What is the formula of the fluoride ion?
F¹⁻
What is the formula of the gallium ion?
Ga³⁺
What is the formula of the iodide ion?
I¹⁻
What is the formula of the lithium ion?
Lī¹⁺
What is the formula of the magnesium ion?
Mg²⁺
What is the formula of the nitride ion?
N³⁻
What is the formula of the oxide ion?
O²⁻
What is the formula of the phosphide ion?
P³⁻
What is the formula of the potassium ion?
K¹⁺
What is the formula of the sodium ion?
Na¹⁺
What is the formula of the strontium ion?
Sr²⁺
What is the formula of the sulfide ion?
S²⁻
Zinc phosphide, Zn₃P₂ is an ionic compound. The formula of the zinc ion is Zn²⁺. Deduce the formula of the phosphide ion
P³⁻
If ammonium nitrate NH₄NO₃ contains the NO₃⁻ ion, what is the formula for the other ion?
NH₄⁺ (ammonium ion)
If calcium carbonate has a Ca²⁺ ion, what is the formula for the other ion?
CO₃²⁻ (carbonate ion)
If copper chloride has the formula CuCl₂, what is the formula of the copper ion?
Cu²⁺
If iron chloride has the formula FeCl₂, what is the formula of the iron ion?
Fe²⁺
If iron chloride has the formula FeCl₃, what is the formula of the iron ion?
Fe³⁺
If iron oxide has the formula Fe₂O₃, what is the name and formula of the iron ion?
iron (III) ion: Fe³⁺
If iron oxide has the formula FeO, what is the formula of the iron ion?
Fe²⁺
If nitric acid (HNO₃) produces H⁺ Ions, what is formula for the other ion?
NO₃⁻ (nitrate ion)
If sulfuric acid (H₂SO₄) produces 2H⁺, what must the other ion be?
SO₄²⁻ (sulfate ion)
If water produces H⁺, what must the other ion be?
OH⁻ (hydroxide ion)
State the formula for the copper (II) ion
Cu²⁺
State the formula for the iron (II) ion
Fe²⁺
State the formula for the iron (III) ion
Fe³⁺
State the formula for the lead (II) ion
Pb²⁺
State the formula of the ammonium ion
NH₄⁺
State the formula of the carbonate ion
CO₃²⁻
State the formula of the hydroxide ion
OH⁻
State the formula of the nitrate ion
NO₃⁻
State the formula of the silver ion
Ag⁺
State the formula of the sulfate ion
SO₄²⁻
State the formula of the zinc ion
Zn²⁺
State the formula of the zinc ion
Zn²⁺
If copper chloride has the formula CuCl₂, what is the formula of the copper ion?
Cu²⁺
If iron chloride has the formula FeCl₂, what is the formula of the iron ion?
Fe²⁺
If iron chloride has the formula FeCl₃, what is the formula of the iron ion?
Fe³⁺
If iron oxide has the formula FeO, what is the formula of the iron ion?
Fe²⁺
State the formula for the copper (II) ion
Cu²⁺
State the formula for the iron (II) ion
Fe²⁺
State the formula for the iron (III) ion
Fe³⁺
State the formula for the lead (II) ion
Pb²⁺
State the formula of the hydrogen ion
H⁺
State the formula of the silver ion
Ag⁺
State the formula of the zinc ion
Zn²⁺
What is the formula for aluminium chloride?
AlCl₃
What is the formula for aluminium nitrate?
Al(NO₃)₃
What is the formula for aluminium oxide?
Al₂O₃
What is the formula for aluminium sulfate?
Al₂(SO₄)₃
What is the formula for aluminium sulfide?
Al₂S₃
What is the formula for ammonium chloride?
NH₄Cl
What is the formula for ammonium sulfide?
(NH₄)₂S
What is the formula for calcium bromide?
CaBr₂
What is the formula for calcium hydroxide?
Ca(OH)₂
What is the formula for calcium nitrate?
Ca(NO₃)₂
What is the formula for calcium nitride?
Ca₃N₂
What is the formula for copper (II) fluoride
CuF₂
What is the formula for copper (II) sulfide?
CuS
What is the formula for iron (II) oxide
FeO
What is the formula for iron (II) phosphide?
Fe₃P₂
What is the formula for iron (III) bromide?
FeBr₃
What is the formula for iron (III) nitride
FeN
What is the formula for lithium carbonate?
Li₂CO₃
What is the formula for lithium chloride?
LiCl
What is the formula for lithium nitride?
Li₃N
What is the formula for magnesium carbonate?
MgCO₃
What is the formula for magnesium chloride?
MgCl₂
What is the formula for magnesium iodide?
MgI₂
What is the formula for magnesium oxide?
MgO
What is the formula for magnesium sulfate?
MgSO₄
What is the formula for potassium bromide?
KBr
What is the formula for potassium chloride?
KCl
What is the formula for potassium hydroxide?
KOH
What is the formula for potassium sulfate?
K₂SO₄
What is the formula for potassium sulfide?
K₂S
What is the formula for silver carbonate?
Ag₂CO₃
What is the formula for silver nitrate?
AgNO₃
What is the formula for silver sulfate?
Ag₂SO₄
What is the formula for sodium chloride?
NaCl
What is the formula for sodium fluoride?
NaF
What is the formula for sodium hydroxide?
NaOH
What is the formula for sodium nitrate?
NaNO₃
What is the formula for sodium oxide?
Na₂O
What is the formula for sodium phosphide?
Na₃P
What is the formula for strontium phospide?
Sr₃P₂
What is the formula for vanadium (V) oxide?
V₂O₅
What is the formula for zinc carbonate?
ZnCO₃
What is the formula for zinc nitrate?
Zn(NO₃)₂
What is the formula for zinc sulfate?
ZnSO₄
What is the formula for aluminium chloride?
AlCl₃
What is the formula for aluminium oxide?
Al₂O₃
What is the formula for aluminium sulfide?
Al₂S₃
What is the formula for calcium bromide?
CaBr₂
What is the formula for calcium nitride?
Ca₃N₂
What is the formula for copper (II) fluoride
CuF₂
What is the formula for copper (II) sulfide?
CuS
What is the formula for iron (II) oxide
FeO
What is the formula for iron (II) phosphide?
Fe₃P₂
What is the formula for iron (III) bromide?
FeBr₃
What is the formula for iron (III) nitride
FeN
What is the formula for lithium chloride?
LiCl
What is the formula for lithium nitride?
Li₃N
What is the formula for magnesium chloride?
MgCl₂
What is the formula for magnesium iodide?
MgI₂
What is the formula for magnesium oxide?
MgO
What is the formula for potassium bromide?
KBr
What is the formula for potassium chloride?
KCl
What is the formula for potassium sulfide?
K₂S
What is the formula for sodium chloride?
NaCl
What is the formula for sodium fluoride?
NaF
What is the formula for sodium oxide?
Na₂O
What is the formula for sodium phosphide?
Na₃P
What is the formula for strontium phospide?
Sr₃P₂
What is the formula for vanadium (V) oxide?
V₂O₅
Draw a dot and cross diagram to show the arrangement of electrons in each of the ions in magnesium chloride, MgCl₂
Draw a dot and cross diagram to show the arrangement of electrons in each of the ions in potassium oxide, K₂O
Draw a dot and cross diagram to show the arrangement of electrons in each of the ions in sodium chloride, NaCl
How can atoms get a full outer shell?
Either the transfer (ionic) or sharing (covalent) of electrons
State the fomula for the two ions in vanadium (V) oxide
V⁵⁺ and O²⁻
Explain the term ionic bond
An ionic bond is the strong electrostatic attraction between oppositely charged ions
State the fomula for the two ions in iron (II) sulfide
Fe²⁺ and S²⁻
What holds ions together?
Ions are held together by a strong electrostatic attraction between the oppositely charged ions
When are ions attracted to each other?
When the ions are oppositely charged
Describe the formation of a covalent bond
The sharing of a pair of electrons between two nuclei
How can atoms get a full outer shell?
Either the transfer (ionic) or sharing (covalent) of electrons
Explain how the atoms are held together in a hydrogen bromide molecule
A shared pair of electrons is attracted to BOTH nuclei
Give the definition of a covalent bond
Strong electrostatic attraction between a shared pair of electrons and two nuclei
Draw a dot and cross diagram to show the covalent bonding in a molecule of ammonia, NH₃
Draw a dot and cross diagram to show the covalent bonding in a molecule of carbon dioxide, CO₂
Draw a dot and cross diagram to show the covalent bonding in a molecule of chlorine, Cl₂
Draw a dot and cross diagram to show the covalent bonding in a molecule of ethane, C₂H₆
Draw a dot and cross diagram to show the covalent bonding in a molecule of ethene, C₂H4
Draw a dot and cross diagram to show the covalent bonding in a molecule of hydrogen chloride, HCl
Draw a dot and cross diagram to show the covalent bonding in a molecule of hydrogen, H₂
Draw a dot and cross diagram to show the covalent bonding in a molecule of methane, CH₄
Draw a dot and cross diagram to show the covalent bonding in a molecule of nitrogen, N₂
Draw a dot and cross diagram to show the covalent bonding in a molecule of oxygen, O₂
Draw a dot and cross diagram to show the covalent bonding in a molecule of water, H₂O
Explain why carbon dioxide gas, CO₂, is a gas at room temperature
Carbon dioxide has a simple molecular structure with weak intermolecular forces that require little energy to overcome
Explain why methane gas, CH₄, is a gas at room temperature
Methane has a simple molecular structure with weak intermolecular forces that require little energy to overcome
Explain why nitrogen gas, N₂, is a gas at room temperature
Nitrogen has a simple molecular structure with weak intermolecular forces that require little energy to overcome
If a substance has a simple molecular structure, what physical state might it be at room temperature?
Gas or liquid (low melting point)
Do larger molecules have higher or lower boiling points than smaller molecules?
Higher
Why is the boiling point of a larger molecule higher than that of a smaller molecule?
Larger molecules have more attractions between them which must be overcome when a substance boils
Why is the melting point of a smaller molecule lower than that of a larger molecule?
Larger molecules have more attractions between them which must be overcome when a substance melts
(Triple only) Draw a diagram to show the bonding in a metal
(Triple only) Describe the bonding in a metal
The strong electrostatic attraction between a regular structure of positive metal ions and a sea of delocalised electrons
(Triple only) Describe the structure of metals
Metals have a giant regular structure of positive metal ions surrounded by a sea of delocalised electrons
(Triple only) Explain why metals are good conductors of electricity
Metals have delocalised electrons which are free to move
(Triple only) Explain why metals are malleable
Metals have layers of ions that can slide over each other
(Triple only) What does the word malleable mean?
able to be hammered or pressed into shape without breaking or cracking
(Triple only) Why do metals have high melting and boiling points?
There is a strong electrostatic attraction between a regular structure of positive metal ions and a sea of delocalised electrons
Complete the equation for the reaction by inserting the state symbols: 2Li(....) + 2H₂O(....) → 2LiOH(...) + H₂(....)
2Li(s) + 2H₂O(l) → 2LiOH(aq) + H₂(g)
How should group 1 elements be stored
Under oil
State 3 observations when lithium reacts with water
1) fizzing occurs 2) lithium moves around 3) lithium disappears 4) lithium floats
State 4 observations when sodium reacts with water
1) fizzing occurs 2) sodium moves around 3) sodium melts 4) sodium disappears 5) sodium floats
State 5 observations when potassium reacts with water
1) fizzing occurs 2) potassium moves around 3) potassium melts 4) lilac flame is seen 5) potassium disappears 6) potassium floats
What are the elements in group 1 called?
Alkali metals
Write the chemical equation for the reaction betweem sodium and water
2Na + 2H₂O → 2NaOH + H₂
If pieces of lithium, potassium and sodium were added to water, how could observations of the differences reactions indicate the relative reactivity of those 3 metals?
Lithium would bubble the least vigorously, showing it is least reactive. Potassium would give off a lilac flame, showing it is most reactive.
If pieces of lithium, potassium and sodium were cut and exposed to air, how could observations of the differences reactions indicate the relative reactivity of those 3 metals?
Potassium would oxidise the most quickly, showing it is most reactive. Lithium would oxidise the slowest, showing it is least reactive.
Describe the relative reactivities of the elements in Group 1
The reactivity increases as you go down the group, e.g. Li<Na<K<Rb
Put these 3 alkali metals in order of reactivity, starting with the least reactive: sodium, rubidium, lithium
lithium, sodium, rubidium
Put these 3 alkali metals in order of reactivity, starting with the most reactive: potassium, francium, lithium
francium, potassium, lithium
Put these 3 alkali metals in order of reactivity, starting with the most reactive: sodium, caesium, rubidium
caesium, rubidium, sodium
Which is less reactive: potassium or caesium?
Potassium
Which is less reactive: sodium or potassium?
Sodium
Which is more reactice: sodium or francium?
Francium
Which is more reactive: lithium or rubidium?
Rubidium
(Triple only) Explain, by referring to the electronic configurations, why lithium is less reactive than sodium.
Sodium has the electronic configuration 2,8,1 and lithium has 2,1. The outer electron lost from sodium is further from the nucleus therefore the electron is less attracted by the nucleus. So sodium is more reactive than lithium
(Triple only) Explain, by referring to the electronic configurations, why potassium is more reactive than sodium.
Sodium has the electronic configuration 2,8,1 and potassium has 2,8,8,1. The outer electron lost from potassium is further from the nucleus therefore the electron is less attracted by the nucleus. So potassium is more reactive than sodium
What are the elements in group 7 called?
Halogens
What colour and state is bromine at room temperature?
red-brown liquid
What colour and state is iodine at room temperature?
dark grey solid
What is the colour and physical state of chlorine at room temperature?
Green gas
Predict what colour and state is astatine at room temperature
black solid
Predict what colour and state is fluorine at room temperature
yellow gas
Suggest how the reactivity of astatine compares to that of iodine. Explain your answer.
Astatine is less reactive because group 7 elements get less reactive with increasing atomic number.
Suggest how the reactivity of fluorine compares to chlorine
Fluorine is more reactive than chlorine as it is higher in the group.
Describe how reactivity changes as you descend group 7
decreases
Hydrogen bromide is reacted with chlorine to form bromine. Write a chemical equation.
2HBr + Cl₂ → 2HCl + Br₂
Identify the element that is displaced in this reaction: 2HBr + Cl₂ → 2HCl + Br₂
Bromine
In halogen displacement reactions, electrons are transferred from one atom to another. How are these reactions classified?
REDOX
Name the substance with the brown colour that forms whem chlorine is added to potassium iodide solution
Iodine as it is less reactive than chlorine
State the colour change observed when bromine is added to an aqueous solution of potassium iodide
Colourless to brown
State the most reactive element in group 7
Fluorine
What type of reaction occurs if you put a chlorine with a solution of sodium bromide?
displacement
Why does chlorine react with hydrogen bromide?
Chlorine is more reactive and so displaces the bromine.
Why would there be no reaction when iodine was added to sodium bromide solution?
Iodine as it is less reactive than bromine
(Triple only) Explain why bromine is less reactive than chlorine
Both chlorine and bromine react by their nucleus attracting an electron to fill their outer shell. The outer shell of bromine is further from the nucleus, so the attraction is weaker, making it less reactive.
(Triple only) Explain, by referring to the electronic configurations, why fluorine is more reactive than chlorine
Fluorine has the electronic configuration 2,7 and chlorine has 2,8,7. An extra outer electron is gained more easily by fluorine. This is because the outer shell is closer to the nucleus, so an extra electron is attracted more strongly.
State the names of the gases present in air and their % by volume
nitrogen = 78%. oxygen = 21%. argon = 0.96%. carbon dioxide = 0.04%
What gas makes up 0.04% of Earth's atomosphere?
carbon dioxide
What gas makes up 78% of Earth's atomosphere?
nitrogen = 78%
What gas makes up around 1% of Earth's atomosphere?
Argon
What percentage of the Earth's atomosphere is oxygen?
21%
Draw a gas syringe
With gas syringes in a closed system, 200cm³ of air is passed back and forward over hot copper until the oxygen is used up. At the end, 160cm³ remains. Calculate the percentage by volume of oxygen in the air.
20%
Are carbon dioxide and sulfur dioxide acidic or basic?
Acidic as carbon and sulfur are non-metals
Hydrogen and helium have both been used in balloons. State one advantage of using helium instead of hydrogen
Helium is not flammable
Name the compound formed when magnesium reacts with oxygen
magnesium oxide
What colour flames to sulfur, carbon and magnesium produce when they burn in air?
Sulfur = blue, Carbon = yellow/orange, Magnesium = white
What happens is a large amount of hydrogen is burnt?
Explosion
What happens when a small amount of hydrogen is burnt in a test tube?
Squeaky pop
What observation is made when carbon burns in air?
Yellow flame
What observation is made when sulfur burns in air?
Blue Flame
What observations are made when magnesium burns in air?
Bright white light. White solid left behind.
When carbon burns in air, is the oxide acidic or basic?
Acidic
When magnesium burns in air, is the oxide acidic or basic?
Basic
When sulfur burns in air, is the oxide acidic or basic?
Acidic
How can metal carbonates be used to produce carbon dioxide?
Themal Decomposition: when metal carbonates are heated, they break down
Write the word and chemical equation for the thermal decompostion of calcium carbonate, CaCO₃
calcium carbonate → calcium oxide + carbon dioxide CaCO₃ → CaO + CO₂
Name the greenhouse gas released from burning hydrocabons
carbon dioxide
Why is carbon dixoxide, CO₂ harmful to the environment?
It is a greenhouse gas and may contribute to global warming
Describe a way in which the rusting of iron could be used to show the approximate percentage of oxygen in air
An excess of wet iron filings in left in a closed system with a known volume of air. After several days the volume of air has fallen as the oxygen is used up. The percentage of oxygen in air is calculates as the change in volume of gas divided by the initial volume (x100%)
Describe how the oxidation of copper can be used to show the approximate percentage of oxygen in air
With gas syringes in a closed system, air is passed back and forward over hot copper until the oxygen is used up. When the volume of gas stops decreasing, the percentage by volume of oxygen in the air is calculated as the change in the volume of gas divided by the initial volume (x100%)
Describe how the reaction of hydrochloric acid and various metals could be used to determine the relative reactivity of those metals
Add the various metals to different test tubes containing the same volume and concentration of acid. The metals which bubble more are more reactive.
If 2 similar test tubes contain acid, and a different metal sample is added to each, how might you tell which metal is more reactive?
More bubbles will appear faster in the test tube with the more reactive metal
An experiment investigates which of metals X and Z is more reactive. The result is X + ZSO₄ → X + ZSO₄. Which metal is more reactive?
Z. There is no reaction.
An experiment investigates which of metals X and Z is more reactive. The result is X + ZSO₄ → XSO₄ + Z. Which metal is more reactive?
X. This is a displacement reaction.
Order these metals from the most reactive to the least: aluminium, calcium, copper, gold, iron, lithium, magnesium, potassium, silver, sodium, zinc
potassium, sodium, lithium, calcium, magnesium, aluminium, zinc, iron, copper, silver, gold
Which is more reactive: copper or magnesium?
magnesium
Which is more reactive: gold or potassium
potassium
Which is more reactive: iron or sodium?
sodium
Which is more reactive: lithium or calcium?
lithium
Which is more reactive: magnesium or aluminium?
magnesium
Which is more reactive: magnesium or lithium?
lithium
Which is more reactive: silver or iron?
iron
Which is more reactive: sodium or copper?
sodium
Which is more reactive: zinc or aluminium?
aluminium
Which is more reactive: zinc or copper
zinc
Describe an experiment to show that iron rusts quicker in salt water than rain water
1) Set up tubes containing iron in rain water and in salt water. 2) Set up control tube with iron and no water. 3) record mass of nails. 4) leave tubes for same length of time. 5) measure mass change of nail. 6) repeat experiment
Describe the conditions under which iron rusts
oxygen and water
Do metals other than iron rust?
No. The term rust is only applied to iron
What is the chemical name of rust?
hydrated iron(III) oxide
Write the word equation for the formation of rust
iron + oxygen + water → hydrated iron (III) oxide
Explain how galvanising prevent rusting
Zinc is more reactive than iron. Zinc reacts with oxygen instead of iron
State the methods of how the rusting of iron may be prevented
grease, oil, paint, plastic and galvanising
What is galvanising?
When zinc is used to coat a less reactive metal to prevent that metal from corrosion
What is sacrificial protection?
Sacrificial protection is when a more reactive metal is connected to a less reactive metal. Only the more reactive metal corrodes, so protecting the less reactive metal
Explain in 2 different ways why rusting is described as an oxidation reaction
iron gains oxygen / iron loses electrons
Identify the species that is oxidised in the following reaction. Explain your answer: 2Br⁻ + Cl₂ → 2Cl⁻ + Br₂
Bromide. Loses electrons
Identify the species that is reduced in the following reaction. Explain your answer: 2Br⁻ + Cl₂ → 2Cl⁻ + Br₂
Chlorine. Gains electrons
If a substance gains oxygen in a reaction how is the process described?
Oxidation
If a substance loses oxygen in a reaction how is the process described?
Reduction
Is the production of iron from iron ore oxidation or reduction?
Reduction
State the meaning of the term oxidising agent
A substance that gives oxygen or removes electrons (it is itself reduced)
State the meaning of the term redox
A reaction involving both reduction and oxidation
State the meaning of the term reducing agent
A substance that takes oxygen or gives electrons (it is itself oxidised)
What is it called when a metal reacts with oxygen in the air to form an oxide layer?
Oxidation
What is reduced in this equation and what is meant by reduction? WO₃ + 3H₂ → W + 3H₂O
Tungsten, W loses oxygen
Write the word equation to represent the reaction between hydrochloric acid and calcium
hydrochloric acid + calcium → calcium chloride + hydrogen
Write the word equation to represent the reaction between sulfuric acid and magnesium
sulfuric acid + magnesium → magnesium sulfate + hydrogen
(Triple only) State 2 properties that makes aluminium suitable for manufacturing aircraft
Low density & resists corrosion
(Triple only) State 2 properties that makes aluminium suitable for power cables
Ductile (drawn into a wire), conducts electricity and low density
(Triple only) State 3 properties that makes iron suitable for saucepans
Good conductor of heat, high melting point and malleable
(Triple only) State a property that makes iron suitable for building
Strong
(Triple only) State two properties of aluminium that make it suitable for use in food cans
Malleable and low density
(Triple only) Apart from being a mixture of metals, what non-metal is often added to alloys to make them stronger?
Carbon
(Triple only) What is a mixture of metals called?
An alloy
(Triple only) What is an alloy?
An alloy is a mixture of a metal and one or more elements, usually other metals or carbon
(Triple only) Alloys contain different sized positive ions. What properties does this give alloys compared to pure metals?
Alloys are harder and less malleable than pure metals
(Triple only) Why are alloys harder than pure metals?
Alloys contain different sized positive ions, so there are no layers of ions to slide over each other
State the colour of litmus in acidic and alkaline solutions
acidic = red alkali = blue
State the colour of methyl orange in acidic and alkaline solutions
acidic = red alkali = yellow
State the colour of phenolphthalein in acidic and alkaline solutions
acidic = colourless alkali = pink
What is the pH of a neutral solution?
7
What is the pH of a strong acid?
0-3
What is the pH of a strong alkali?
11-14
What is the pH of a weak acid?
4-6
What is the pH of a weak alkali?
8-10
What is the typical range of the pH scale?
0-14
What scale typically ranges between 0 and 14?
pH scale
With universal indicator, what is the pH of a blue solution?
8-10
With universal indicator, what is the pH of a green solution?
7 (neutral)
With universal indicator, what is the pH of a purple solution?
11-14
With universal indicator, what is the pH of a red solution?
0-3
With universal indicator, what is the pH of a yellow solution?
4-6
What is the universal indicator colour of a neutral solution?
Green
What is the universal indicator colour of a pH 0-3 solution?
Red
What is the universal indicator colour of a pH 11-14 solution?
Purple
What is the universal indicator colour of a pH 4-6 solution?
Yellow
What is the universal indicator colour of a pH 7 (neutral) solution?
Green
What is the universal indicator colour of a pH 8-10 solution?
Blue
What is the universal indicator colour of a strongly acid solution?
Red
What is the universal indicator colour of a strongly alkali solution?
Purple
What is the universal indicator colour of a weakly acid solution?
Yellow
What is the universal indicator colour of a weakly alkali solution?
Blue
What is an acid?
An acid is a source of hydrogen ions, H⁺
What is an alkali?
An alkali is a source of hydroxide ions, OH⁻
Can a base neutralise an acid?
Yes
What is a base?
A substance which can neutralise an acid, forming salt and water only
(Triple only) Describe how to carry out an acid-alkali titration
1) Pipette 25cm³ of alkali into a conical flask. 2) Add indicator. 3) Fill a burette with acid, record the initial volume. 4) Whilst swirling the flask, add the acid dropwise until the indicator changes colour. 5) Record the volume and calculate the volume of acid which was added. 6) Repeat until two concordant results (within 0.2cm³ of each other). 7) Result is the average of all concordant results.
(Triple only) Draw a burette
(Triple only) Draw a pipette
Is aluminium carbonate soluble?
no
Is aluminium chloride soluble?
yes
Is aluminium nitrate soluble?
yes
Is aluminium sulfate soluble?
yes
Is ammonium carbonate soluble?
yes
Is ammonium chloride soluble?
yes
Is ammonium nitrate soluble?
yes
Is ammonium sulfate soluble?
yes
Is barium carbonate soluble?
no
Is barium chloride soluble?
yes
Is barium nitrate soluble?
yes
Is barium sulfate soluble?
no
Is calcium carbonate soluble?
no
Is calcium chloride soluble?
yes
Is calcium nitrate soluble?
yes
Is calcium sulfate soluble?
no
Is copper carbonate soluble?
no
Is copper chloride soluble?
yes
Is copper nitrate soluble?
yes
Is copper sulfate soluble?
yes
Is iron carbonate soluble?
no
Is iron chloride soluble?
yes
Is iron nitrate soluble?
yes
Is iron sulfate soluble?
yes
Is lead carbonate soluble?
no
Is lead chloride soluble?
no
Is lead nitrate soluble?
yes
Is lead sulfate soluble?
no
Is magnesium carbonate soluble?
no
Is magnesium chloride soluble?
yes
Is magnesium nitrate soluble?
yes
Is magnesium sulfate soluble?
yes
Is potassium carbonate soluble?
yes
Is potassium chloride soluble?
yes
Is potassium nitrate soluble?
yes
Is potassium sulfate soluble?
yes
Is silver carbonate soluble?
no
Is silver chloride soluble?
no
Is silver nitrate soluble?
yes
Is silver sulfate soluble?
yes
Is sodium carbonate soluble?
yes
Is sodium chloride soluble?
yes
Is sodium nitrate soluble?
yes
Is sodium sulfate soluble?
yes
Is zinc carbonate soluble?
no
Is zinc chloride soluble?
yes
Is zinc nitrate soluble?
yes
Is zinc sulfate soluble?
yes
State the solubility rule for carbonates salts
all carbonates are insoluble, except those of sodium, potassium and ammonium
State the solubility rule for chloride salts
all are soluble, except silver chloride
State the solubility rule for nitrate salts
all nitrates are soluble
State the solubility rule for sodium, potassium and ammonium salts
all common sodium, potassium and ammonium salts are soluble
State the solubility rule for sulfate salts
all sulfates are soluble, except those of barium and calcium
What is defined as a proton acceptor?
An alkali
What is defined as a proton donor?
An acid
An acid is called a proton _________
An acid is a proton donor
An alkali is called a proton _________
An alkali is a proton acceptor
acid + alkali →
acid + alkali → salt + water
acid + base →
acid + base → salt + water
acid + metal →
acid + metal → salt + hydrogen
acid + metal carbonate →
acid + metal carbonate → salt + carbon dioxide + water
Describe the observations of the reaction of aluminium and dilute hydrochloric acid
fizzing and metal disappears
Describe the observations of the reaction of calcium carbonate and dilute hydrochloric acid
fizzing and solid disappears
Describe the observations of the reaction of magnesium and dilute sulfuric acid
fizzing and metal disappears
Describe the observations of the reaction of zinc and dilute hydrochloric acid
fizzing and metal disappears
Give the formula of sulfuric acid
H₂SO₄
Give the name of the substance which has formula HNO₃
nitric acid
Give the name of the substance which has the formula HCl (aq)
hydrochloric acid
hydrochloric acid + magnesium →
hydrochloric acid + magnesium → magnesium chloride + hydrogen
hydrochloric acid + sodium hydroxide →
hydrochloric acid + sodium hydroxide → sodium chloride + water
nitric acid + calcium carbonate →
nitric acid + calcium carbonate → calcium nitrate + carbon dioxide + water
sulfuric acid + copper oxide →
sulfuric acid + copper oxide → copper sulfate + water
What two observations can be made when a metal reacts with an acid?
Bubbles. Metal disappears.
Write the word equation to represent the reaction between copper oxide and sulfuric acid
sulfuric acid + copper oxide → copper sulfate + water
Write the word equation to represent the reaction between nitric acid and copper carbonate
nitric acid + copper carbonate → copper nitrate + carbon dioxide + water
Is ammonia acidic or basic?
Basic
Is iron (III) hydroxide acidic or basic?
Basic (as metal hydroxides are basic)
Is magnesium oxide acidic or basic?
Basic (as magnesium is a metal)
What is an alkali compared to a base?
Alkalis are bases that are soluble in water
A pure, dry sample of a soluble salt can be prepared starting with an insoluble reactant. What is this method called?
Excess solid method
Describe the method to prepare a pure dry sample of copper sulfate (soluble salt)
1) Heat acid in a beaker. 2) Add base until excess and stir with glass rod. 3) Filter the mixture using filter paper and funnel. 4) Heat the filtered solution (filtrate) until a hot saturated solution forms. 5) Allow the solution to cool so that hydrated crystals form. 6) Remove the crystals by filtration and wash with distilled water. 7) Dry by leaving in a warm place.
(Triple only) A pure, dry sample of a soluble salt can be prepared starting from an acid and alkali. What are the two stages of this method called?
Titration then crystallisation
(Triple only) Describe the method to prepare a pure dry sample of sodium chloride (soluble salt)
1) Pipette 25cm³ of alkali into a conical flask. 2) Do not add indicator. 3) (Using titration values)Titrate the known volume acid into conical flask containing alkali. 4) Transfer to an evaporating basin. 5) Heat the solution until a hot saturated solution forms. 6) Allow the solution to cool so that hydrated crystals form. 7) Remove the crystals by filtration and wash with distilled water. 8) Dry by leaving in a warm place.
(Triple only) A pure, dry sample of an insoluble salt can be prepared starting with two soluble reactants. What is this method called?
Precipitation method
(Triple only) Describe an experiment to prepare a pure, dry sample of an insoluble salt, starting from two soluble reactants
1) Mix the two salt solutions together in a beaker. 2) Stir with glass rod. 3) Filter using filter paper and funnel. 4) Wash with distilled water. 5) Dry by leaving in a warm place.
When preparing hydrated copper(II) sulfate crystals starting from copper(II) oxide, why is an excess of copper (II) oxide added?
To ensure all the acid has reacted so there is no acid left
When preparing hydrated copper(II) sulfate crystals starting from copper(II) oxide, why is the acid gently heated?
To speed up the reaction
(Triple only) What method would be followed to prepare a sample of pure, dry lead (II) sulfate?
Precipitation method
A gas is bubbled through limewater and the limewater goes cloudy. Identify the gas.
Carbon dioxide
Describe the test for ammonia gas
Turns damp red litmus paper blue
Describe the test for carbon dioxide gas
Bubble the gas through limewater and see if it goes cloudy
Describe the test for chlorine gas
Turns moist litmus paper white (bleaches)
Describe the test for hydrogen gas
Use a lit splint to see if the gas pops
Describe the test for oxygen gas
Use a glowing splint and see if it relights
In the test of a gas, a glowing splint relights. What is the gas?
Oxygen
In the test of a gas, a lit splint gives a squeaky pop. What is the gas?
Hydrogen
Which gas will bleach moist litmum paper?
Chlorine
Which gas will turn damp red litmus paper blue?
Ammonia
A gas is bubbled through limewater and the limewater goes cloudy. Identify the gas.
Carbon dioxide
Describe the test for carbon dioxide gas
Bubble the gas through limewater and see if it goes cloudy
Describe the test for hydrogen gas
Use a lit splint to see if the gas pops
In the test of a gas, a lit splint gives a squeaky pop. What is the gas?
Hydrogen
Describe how you would carry out a flame test
Put solid onto a wire. Put into a blue flame
In a flame test, why is hydrochloric acid used?
To clean the wire of any unwanted ions
How are calcium ions identified, and what is the result?
Using a flame test. Flame colour is orange-red
How are lithium ions identified, and what is the result?
Using a flame test. Flame colour is red
How are potassium ions identified, and what is the result?
Using a flame test. Flame colour is lilac
How are sodium ions identified, and what is the result?
Using a flame test. Flame colour is yellow
In a flame test, a blue-green colour is seen. Give the formula of the cation which is present.
Cu²⁺
In a flame test, a orange-red colour is seen. Give the formula of the cation which is present.
Ca²⁺
In a flame test, a red colour is seen. Give the formula of the cation which is present.
Li⁺
In a flame test, a lilac colour is seen. Give the formula of the cation which is present.
K⁺
In a flame test, a yellow colour is seen. Give the formula of the cation which is present.
Na⁺
In the flame test for copper (II) ions what colour is the result?
Blue-green
Give the name of the blue precipitate formed when sodium hydroxide is added to a solution containing Cu²⁺
copper (II) hydroxide
Give the name of the brown precipitate formed when sodium hydroxide is added to a solution containing Fe³⁺
iron (III) hydroxide
Give the name of the green precipitate formed when sodium hydroxide is added to a solution containing Fe²⁺
iron (II) hydroxide
How would you test for the ammonium ion (NH₄⁺)?
Add sodium hydroxide. If ammonium ions were present, ammonia gas will form which will turn damp red litmus paper blue
What is the test for copper (II) ions (Cu²⁺) and what is the result?
Add NaOH. A blue precipitate forms.
What is the test for iron (II) ions (Fe²⁺) and what is the result?
Add NaOH. A green precipitate forms.
What is the test for iron (III) ions (Fe³⁺) and what is the result?
Add NaOH. A brown precipitate forms.
What is the test for NH₄⁺ ions and what is the result?
Add NaOH. The gas (ammonia) turns damp red litmus paper blue.
When NaOH is added to a sample, a blue precipitate forms. What cation was present in the sample?
Copper (II), Cu²⁺
When NaOH is added to a sample, a brown precipitate forms. What cation was present in the sample?
Iron (III), Fe³⁺
When NaOH is added to a sample, a green precipitate forms. What cation was present in the sample?
Iron (II), Fe²⁺
When NaOH is added to a sample, the resultant gas turns damp red litmus paper blue. What cation was present in the sample?
Ammonium, NH₄⁺
Write a word equation for the reaction between sodium hydroxide and iron(II) sulfate
sodium hydroxide + iron(II) sulfate → iron (II) hydroxide + sodium sulfate
After adding nitric acid and silver nitrate to a solution containing bromide ions, what colour precipitate is formed?
A cream precipitate (of silver bromide) is formed
After adding nitric acid and silver nitrate to a solution containing chloride ions, what colour precipitate is formed?
A white precipitate (of silver chloride) is formed
After adding nitric acid and silver nitrate to a solution containing iodide ions, what colour precipitate is formed?
A yellow precipitate (of silver iodide) is formed
Describe how you would test for carbonate ions (CO₃²⁻) and what is the result if they are present?
Add nitric acid and see if carbon dioxide bubbles form
Describe how you would test for sulfate ions (SO₄²⁻) and what is the result if they are present?
Add dilute HCl, followed by barium chloride (BaCl₂). A white precipitate will form
Describe the test for bromide ions
Add dilute nitric acid and silver nitrate. A cream precipitate of silver bromide is formed.
In the test for carbonate ions, what is added to the sample?
nitric acid (HNO₃)
In the test for carbonate ions, what result shows they are present?
bubbles form
In the test for sulfate ions, what result shows they are present?
A white precipitate is formed
In the test for sulfate ions, what two substances are added to the sample?
hydrochloric acid (HCl) and then barium chloride (BaCl₂)
What 2 things are added to a solution to test for chloride ions? What is observed if they are present?
Add dilute nitric acid and silver nitrate. A white precipitate of silver chloride is formed.
When testing a sample for ions, hydrochloric acid and then barium chloride are added to a sample. A white precipitate forms. What ions have been shown to be present?
sulfate ions (SO₄²⁻)
When testing a sample for ions, hydrochloric acid and then barium chloride are added to a sample. A white precipitate forms. What is the name of that precipitate?
barium sulfate
When testing a sample for ions, nitric acid is added to a sample and then bubbles are seen. What ions have been shown to be present?
carbonate ions (CO₃²⁻)
When testing a sample of ammonium iodide, nitric acid and then silver nitrate is added. What is the result, and name the substance formed?
A yellow precipitate of silver iodide
When testing a sample of lithium bromide, nitric acid and then silver nitrate is added. What is the result, and name the substance formed?
A cream precipitate of silver bromide
When testing a sample of potassium chloride, nitric acid and then silver nitrate is added. What is the result, and name the substance formed?
A white precipitate of silver chloride
When testing for halide ions, after silver nitrate is added to a sample a cream precipitate is formed. Give the formula of the anion present in the sample.
Br⁻
When testing for halide ions, after silver nitrate is added to a sample a white precipitate is formed. Give the formula of the anion present in the sample.
Cl⁻
When testing for halide ions, after silver nitrate is added to a sample a yellow precipitate is formed. Give the formula of the anion present in the sample.
I⁻
When testing for halide or sulfate ions, why is acid added added first?
to remove any carbonate ions
Which two substances are added when testing for halide ions, and what is the result if they are present?
Add dilute nitric acid and silver nitrate
Which two substances are added when testing for the sulfate (SO₄²⁻) ions? (2)
Add dilute HCl, followed by barium chloride (BaCl₂)
Write an chemical equation for the reaction between barium chloride and lithium sulfate (Li₂SO₄). Include state symbols. Also, what would you see?
BaCl₂ (aq) + Li₂SO₄ (aq) → BaSO₄ (s)+ 2LiCl (aq). Observe a white precipitate of barium sulfate.
Describe the chemical test for water
Add water to anhydrous copper(II) sulfate which will change from white to blue if water is present
What colour is anhydrous copper (II) sulfate?
White
What colour is hydrated copper (II) sulfate?
Blue
Describe a test to show whether water is pure
Heat the sample and measure the temperature. If the sample is pure water it will boil at 100⁰C
What is meant by the term endothermic?
A reaction in which heat energy is taken in (surroundings get colder)
What is meant by the term exothermic?
A reaction in which heat energy is given out (surroundings get hotter)
Explain why experimental values of enthalpy change differ from theoretical values
Heat energy is lost to the surroundings. Not all the reactants are used up.
In a calorimetry experiment to investigate the heat energy released by the combustion of ethanol, why should the water in the calorimeter be stirred?
To ensure the heat energy is mixed evenly throughout all the water
Use Q=mcΔT and c=4.18J/°C/g. 25cm³ of sulfuric acid is put into a boiling tube. The starting temperature is 21°C. A spatula of iron filings is added. After a while the temperature reaches 33°C. What is the total heat energy change?
1254 J
Use Q=mcΔT and c=4.18J/°C/g. A spatula of sodium fluoride is put into a boiling tube with 25cm³ of water. The temperature drops from 22.0°C to 18.6°C. What is the total heat energy change?
-355 J
Use Q=mcΔT and c=4.18J/°C/g. A strip of magnesium is added to a beaker with 200cm³ of copper (II) sulfate. The temperature starts at 21.7°C and rises to a maximum of 23.1°C. What is the total heat energy change?
1170 J
In a combustion calorimetry experiment, 0.78g of ethanol (C₂H₅OH) produced 12,540 J of heat energy. Calculate the molar enthalpy change.
738 kJ/mol
State the units of molar enthalpy change.
kJ/mol
(Triple only) Draw an energy level diagram for an endothermic reaction and use ΔH to represent the enthalpy change
(Triple only) Draw an energy level diagram for an exothermic reaction and use ΔH to represent the enthalpy change
(Triple only) What does the symbol ΔH mean
enthalpy (energy) change
(Triple only) Explain, in terms of making and breaking bonds, why a reaction could be endothermic
The energy need to break the bonds is more than the energy released to make the bonds
(Triple only) Explain, in terms of making and breaking bonds, why a reaction could be exothermic
The energy need to break the bonds is less than the energy released to make the bonds
(Triple only) In an endothermic reaction, which takes more energy: the breaking of bonds or the making of new bonds?
Breaking bonds
(Triple only) In an exothermic reaction, which takes more energy: the breaking of bonds or the making of new bonds?
Making new bonds
(Triple only) Is breaking bonds exothermic or endothemic?
Endothermic
(Triple only) Is making new bonds exothermic or endothemic?
Exothermic
(Triple only) Assuming bond energies in kJ/mol: H-C 412, C-C 348, O-H 463, C-O 360, C=C 612. Calculate the molar enthalpy change for the reaction: ethanol → ethene + water
+45 kJ/mol
(Triple only) In a chemical reaction, 250 kJ/mol is taken to break all the bonds and 280 kJ/mol is released when new bonds are formed. What is the overall molar enthalpy of the reaction?
-30 kJ/mol
(Triple only) In a chemical reaction, the overall molar enthalpy is +87 kJ/mol. Is this reaction exothermic or endothermic?
Endothermic
(Triple only) In a chemical reaction, the overall molar enthalpy is -87 kJ/mol. Is this reaction exothermic or endothermic?
Exothermic
Are combustion reactions exothermic or endothermic?
Exothermic
Are displacement reactions exothermic or endothermic?
Exothermic
Are neutralisation reactions exothermic or endothermic?
Exothermic
When a solid dissolves, is this process exothermic or endothermic?
Endothermic
Calcium carbonate reacts with an excess of hydrochloric acid to produce carbon dioxide. Sketch a graph to show the total volume of gas produced over time. Add a line to show the total volume if half the mass of calcium carbonate is used.
Draw a diagram to explain that a catalyst provides an alternative pathway with lower activation energy.
Mg + 2HCl → MgCl₂ + H₂ Assume acid is in excess. Sketch a graph showing total gas produced over time. Add a second line showing if double the concentration of acid is used.
Mg + 2HCl → MgCl₂ + H₂ Sketch a graph showing total gas produced over time. Add a second line showing if a lower temperature is used
Mg ribbon and an excess of HCl react to product a gas. Sketch a graph showing the total volume of gas over time. Add a second line for using powdered magnesium.
The reaction between magnesium and hydrochloric acid was used to measure the rate of reaction at different temperatures. Name 4 things which should be kept constant.
Temperature of acid. Volume of acid. Concentration of acid. Mass of magnesium. Surface area of magnesium.
On a graph showing gas produced (verticle axis) over time (horizontal axis), how does the line tell us the rate of reaction?
The steeper the line, the faster the rate of reaction
State 5 ways in which the rate of reaction could be increased
Increase surface area (solids), increase temperature, increase concentration (solutions), increase pressure (gases), add an appropriate catalyst
What happens to the rate of reaction if a catalyst is added?
Rate of reaction increases
What happens to the rate of reaction if the concentration of solutions is INCREASED?
Rate of reaction increases
What happens to the rate of reaction if the pressure of gases is INCREASED?
Rate of reaction increases
What happens to the rate of reaction if the surface area of a solid is INCREASED?
Rate of reaction increases
What happens to the rate of reaction if the temperature is INCREASED?
Rate of reaction increases dramatically
What simple change could be made to a reaction to speed it up dramatically?
Heat it up
What happens to the rate of reaction if the temperature is INCREASED?
Rate of reaction increases dramatically
What simple change could be made to a reaction to speed it up dramatically?
Heat it up
Explain the effects of increasing the concentration of solutions on the rate of a reaction in terms of particle collision theory
1) more particles in same space 2) more frequent collisions 3) increase rate of reaction
Explain the effects of increasing the pressure of gases on the rate of a reaction in terms of particle collision theory
1) more particles in same space 2) more frequent collisions 3) increase rate of reaction
Explain the effects of increasing the surface area of a solid on the rate of a reaction in terms of particle collision theory
1) more particles exposed 2) more frequent collisions 3) increase rate of reaction
Explain the effects of increasing the temperature on the rate of a reaction in terms of particle collision theory
1) particles have more kinetic energy 2) more frequent collisions 3) and a higher proportion of the collisions which occur have greater or equal to the activitation energy 4) increase rate of reaction
What is a catalyst?
A substance that speeds up a chemical reaction but is chemically unchanged at the end of the reaction
What type of substance speeds up a chemical reaction but is chemically unchanged at the end of the reaction?
Catalyst
Explain how a catalyst works
A catalyst provides an alternative pathway with lower activation energy
(Triple only) What happens if two particles collide with less than the activation energy
No reaction
(Triple only) What is meant by the term activation energy?
The minimum energy that the particles in collision must have if a reaction is going to occur
(Triple only) With how much energy must two particles collide for a reaction to occur?
The particles must collide with an energy greater or equal to the activation energy
Give a simple reaction can be used to investigate the effect of changing concentration on the rate of reaction
Marble chips added to hydrochloric acid of various concentrations
Give a simple reaction can be used to investigate the effect of changing surface area on the rate of reaction
hydrochloric acid added to either marble chips of powdered caclium carbonate
Describe the laboratory preparation of oxygen from hydrogen peroxide
Hydrogen peroxide is added to a flask containing a catalyst of manganese oxide, MnO₂. Oxygen is produced and is collected underwater.
State the catalyst used for making oxygen through the decomposition of hydrogen peroxide
manganese(IV) oxide, MnO₂
What reactant is used to produce a sample of oxygen in the lab?
hydrogen peroxide
Write the chemical equation for the decompostion of hydrogen peroxide, H₂O₂
2H₂0₂ → 2H₂0 + O₂
Write the word equation for the decompostion of hydrogen peroxide, H₂O₂
hydrogen peroxide → water + oxygen
Explain the term hydrocarbon
A hydrocarbon is a molecule containing only hydrogen and carbon
Show the empirical formulae, molecular formulae, general formulae, structural formulae and displayed formulae of butane
Show the empirical formulae, molecular formulae, general formulae, structural formulae and displayed formulae of ethane
What is a general formula?
A formula to show the relative quantity of different types of atom for a molecules in a homologous series. Eg CnH2n+2 for alkanes
Explain the term functional group
A functional group is an atom or a group of atoms that determine the chemical properties of a compound
Explain the term homologous series
A homologous series is a family of compounds with 1) the same general formula 2) similar chemical properties 3) trends in their physical properties
What are isomers?
Molecules with the same molecular formula but with a different structure
Explain the term homologous series
A homologous series is a family of compounds with 1) the same general formula 2) similar chemical properties 3) trends in their physical properties
Explain the term isomerism
Molecules with the same molecular formula but with a different structure
Draw the displayed formula for 2,2-dimethyl hexane
Draw the displayed formula for 2,3-dimethyl hexane
Draw the displayed formula for 2-methyl hexane
Draw the displayed formula for 4-ethyl octane
Draw the displayed formula for 4-methylpent-2-ene
Write all the possible different structural and displayed formulae of C₄H₁₀
Write all the possible different structural and displayed formulae of C₄H₈
Write all the possible different structural and displayed formulae of C₅H₁₂
In what type of reaction is an atom or group of atoms added to a molecule without taking anything away?
Addition reaction
In what type of reaction is an atom or group of atoms replaced by a different atom or group of atoms?
Substitution reaction
What is a substitution reaction?
A reaction where an atom or group of atoms is replaced by a different atom or group of atoms
What is an addition reaction?
A reaction where an atom or group of atoms is added to a molecule without taking anything away
What is combustion?
Combustion is burning a substance, and is a reaction with oxygen
What is crude oil?
A mixture of hydrocarbons
Explain how crude oil is separated into fractions
Crude oil is separated by fractional distillation. Crude oil is heated and the oil evaporates. It then goes into the tower. As the vapours rise up the tower the temperature falls. Different sized fractions condense at different heights because they have different boiling points. Smaller molecules condense high up the tower. Larger molecules condense low down in the tower. Then the fractions are collected.
What is the name of the process in which crude oil is separated into its various components?
Fractional distillation
Recall a use for each of the 6 fractions obtained from the fractional distillation of crude oil
refinery gases=cooking; gasoline=fuel for cars; kerosene=fuel for planes; diesel=fuel for lorries; fuel oil=fuel for ships; bitumen=surfacing roads
Recall a use of bitumen
Surfacing roads
Recall a use of diesel
Fuel for lorries
Recall a use of fuel oil
Fuel for ships
Recall a use of gasoline
Fuel for cars
Recall a use of kerosene
Fuel for aeroplanes
Recall a use of refinery gases
Cooking
Recall the names of the main fractions obtained from crude oil, in order of lowest boiling point first
Refinery gases, gasoline, kerosene, diesel, fuel oil and bitumen
Describe the trend in boiling points of the main fractions in crude oil
Boiling point increases as the number of carbon atoms (chain length) increase
Describe the trend in viscosity of the main fractions in crude oil
Viscosity increases as the number of carbon atoms (chain length) increase
In the fractional distillation of crude oil, how does boiling point change as the chains get longer?
Increases
In the fractional distillation of crude oil, how does viscosity change as the chains get longer?
Increases
What does volatile mean? Which fraction of crude oil is the most volatile?
If a substance is volatile it evaporates easily. Refinery gas is the most volatile fraction of crude oil.
What is meant by the term viscosity?
The viscosity of a fluid describes how easily it flows. Water has a low viscosity, it flows very easily. Crude oil has a higher viscosity than water, it does not flow very easily.
Which fraction of crude oil has the lowest boiling point?
Refinery gases
Which fraction of crude oil is the most viscous?
Bitumen
What is a fuel?
A fuel is a substance that, when burned, releases heat energy
What is a substance called if it, when burned, releases heat energy?
A fuel
Recall the products of the complete combustion of alkanes
Carbon dioxide and water
Recall the products of the incomplete combustion of alkanes
Carbon, carbon monoxide, carbon dioxide and water
What is produced when alkanes burn with insufficient oxygen?
Carbon monoxide and water (and possibly also carbon and carbon dioxide)
Write a chemical equation for the complete combustion of propane
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Explain why carbon monoxide is dangerous to humans
It is poisonous because it reduces the capacity of the blood to carry oxygen
Why does incomplete combustion occur?
When there is an insufficient supply of oxygen for complete combustion
In car engines, sparks cause the formation of some gases which contribute to acid rain. What are these gases?
Oxides of nitrogen
What is produced when nitrogen reacts with oxygen?
Nitrogen oxides
Why can nitrogen react with oxygen in a car engine?
The temperature is very high
How does sulfur dioxide form in car engines?
Petrol includes the impurity sulfur, and when the petrol combusts some sulfur dioxide is formed
Describe how nitrogen oxides and sulfur dioxide contribute to acid rain
Nitrogen oxides created in hot car engines and sulfur dioxide released when fossil fuels are burned combine with water in the atmosphere to form acidic solutions
Describe the problems caused by acid rain
Acid rain damages plant life and life in lakes. It also corrodes limestone and some metals.
State the problem associated with sulfur dioxide in the atomosphere?
The sulfur dioxide combines with water in the atmosphere to form acidic solutions (acid rain)
Write the chemical equation for sulfur dioxide dissolving in water to form acid rain
SO₂ + H₂O → H₂SO₃
State the catalyst for the cracking of hydrocarbons
Aluminium oxide
State the conditions for the cracking of hydrocarbons
Aluminium oxide catalyst heated to 600°C
State the temperature for the cracking of hydrocarbons
600°C
What is cracking?
The breaking down of long-chain alkanes into alkenes and shorter-chain alkanes
When long chain alkanes are cracked, what is produced?
Shorter chain alkanes and alkenes
Write a chemical equation for the cracking of decane
C₁₀H₂₂ → C₂H₄ + C₈H₁₈
Crude oil contains a surplus of long chain alkanes and there is much higher demand for shorter chain alkanes. What process is used to deal with this imbalance?
Cracking
Explain why cracking is an important process in the oil industry
Cracking converts long chain hydrocarbons into short chain hydrocarbons. Crude oil contains a surplus long chains. Shorter chain hydrocarbons are in greater demand, e.g. petrol. Cracking also produces alkenes which are used in making polymers and ethanol.
State the general formula of alkanes
CnH2n+2
State the names and molecular formulae of the first 5 alkanes
methane (CH₄), ethane (C₂H₆), propane (C₃H₈), butane (C₄H₁₀), pentane (C₅H₁₂)
Explain the term saturated
A molecule containing only single bonds
Why are alkanes classified as saturated hydrocarbons?
They contain only single bonds
Draw the displayed formula for the two alkanes with the molecular formula C₄H₁₀
Draw the displayed formulae for butane
Draw the displayed formulae for ethane
Draw the displayed formulae for methane
Draw the displayed formulae for pentane
Draw the displayed formulae for propane
What is the molecular formula for butane?
C₄H₁₀
What is the molecular formula for ethane?
C₂H₆
What is the molecular formula for hexane?
C₆H₁₄
What is the molecular formula for methane?
CH₄
What is the molecular formula for pentane?
C₅H₁₂
What is the molecular formula for propane?
C₃H₈
State the conditions for the reaction of methane with bromine to form bromomethane
UV light
What are the two products of the reaction between methane and bromine? (2)
Bromomethane (CH₃Br) and hydrogen bromide (HBr)
What else is needed for methane to react with bromine?
UV light
What is the name given to the type of reaction that occurs when ethane reacts with bromine under UV light
Substitution
Would methane normally react with bromine?
No (because it is saturated)
Write the chemical equation for the reaction between methane and bromine
CH₄ + Br₂ → CH₃Br +HBr
Write the word equation for the reaction between methane and bromine
methane + bromine → bromomethane + hydrogen bromide
Of which homologous series is >C=C< (a carbon-to-carbon double bond) the functional group?
Alkenes
What is the functional group of an alkene?
>C=C< (a carbon-to-carbon double bond)
State the general formula for alkenes
CnH2n
Explain the term unsaturated
A molecule containing a carbon-carbon double bond
Why are alkenes classified as unsaturated hydrocarbons?
They contain a double bond
Draw the displayed formulae for butene
Draw the displayed formulae for ethene
Draw the displayed formulae for propene
Draw the displayed formulae for the two straight chain isomers of butene. Name these two isomers
State the names and molecular formulae of the first 3 alkenes
ethene (C₂H₄), propene (C₃H₆), butene (C₄H₈)
What is the molecular formula for butene?
C₄H₈
What is the molecular formula for ethene?
C₂H₄
What is the molecular formula for propene?
C₃H₆
State the colour change in the reaction of an alkene with bromine water
Orange to colourless
State the colour change when an alkane is mixed with bromine water
No change
What is produced when an alkene reacts with bromine?
A dibromoalkane
What two things can be added together to produce a dibromoalkane?
An alkene and bromine
What type of reaction takes place when bromine reacts with an alkene?
Addition
When bromine is added, what happens to an alkane?
Nothing (the sample remains orange)
When bromine is added, what happens to an alkene?
The sample turns from orange to colourless.
Bromine is added to a sample of an alkane and also to a sample of an alkene. Describe the result of each.
With the alkane, no change (stays brown). With the alkene, changes from brown to colourless
What is used to test if something is an alkane or and alkene?
Bromine water
Describe, in terms of structure and bonding, what happens when ethene molecules are converted into poly(ethene)
One bond in the double bond breaks. Monomers join together to form a long chain. Polymer contains only single bonds
Explain what is a monomer
Monomers are the many small molecules (such as ethene) which add together to make a polymer
Explain what is an addition polymer
An addition polymer is large molecule made by adding many small molecules (each containing a double bond) to form one much larger molecule
What is the process of joining monomers together called?
Polymerisation
Draw the equation to show the formation of poly(ethene)
Draw the equation to show the formation of poly(propene)
Draw the repeating unit for poly(but-1-ene)
Draw the repeating unit for poly(but-2-ene)
Draw the repeating unit for poly(chloroethene)
Draw the repeating unit for poly(ethene)
Draw the repeating unit for poly(propene)
Draw the displayed formula of the monomer used to make poly(but-1-ene)
Draw the displayed formula of the monomer used to make poly(but-2-ene)
Draw the displayed formula of the monomer used to make poly(ethene)
Draw the displayed formula of the monomer used to make poly(propene)
Explain why addition polymers are hard to dispose of
They are inert as they have strong C-C bonds. This makes them non-biodegradeable.
What is meant by the term biodegradable?
The break down of a substance by microorganisms