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79 terms

Chemistry Mid Term Review

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a chemical can be defined as...
any substabce that has a definite composition
an atom is...
the smallest unit of matter that maintains its chemical identity
a compound is...
a substance, made of two or more atoms that are chemically bonded, that can be broken down into simpler, stable substances.
Which of the following is not a physical change? (a.grinding, b.cutting,c.boiling,d.burning)
burning
noble gasses are in Group 18, and are best known because they are...
unreactive
a state of matter in which a material has no definite shape but has a definite volume is the ________ state
liquid
the liquid state of mater can be described as...
having a definite volume but not a definite shape
a solid substance is...
always the same shape regardless of its container
What happens to the energy in a substance when it changes state?
it changes form, but is neither destroyed nor increased.
A mixture is...
a blend of any two or more kinds of matter, as long as each maintains its own unique properties
The vertical columns on the periodic table are called...
groups
The horizontal rows on the periodic table are called...
periods
A nonmetal is usually...
brittle
Metalloids are often...
semiconductors
A statement that can be tested experimentally is a...
hypothesis
The symbols for units of length in order from largest to smallest are...
km, m, cm, mm
The relationship between the mass m of a material, its volume V, and its density D is...
D=m/V
A sample of gold has a mass of 96.5 g and a volume of 5.00 cm3. The density of gold is...
19.3 g/cm3
What is the density of 37.72 g of material whose volume is 6.80 cm3?
5.55 g/cm3
1.06 L of water is equivalent to...
1060 mL
If 1 inch equals 2.54 cm, how many centimeters equal 1 yard?...
91.4 cm
A measurement that closely agrees with an accepted value is best described as...
accurate
A numerical result is said to have good precision if...
repeated measurements agree closely
The number of significant figures in the measured value 0.032 g is...
3
Which of these measurements has been expressed to three significant figures?...
.202
When 64.4 is divided by 2.00, the correct number of significant figures in the result is...
3
The speed of light is 300 000 km/s. In scientific notation, this speed is written to one significant figure as...
3 x 10^5 km/s
When 6.02 x 1023 is multiplied by 9.1 x 10^-31, the product is...
5.4 x 10-7
According to the law of conservation of mass, when sodium, hydrogen, and oxygen react to form a compound, the mass of the compound is _____ the sum of the masses of the individual elements...
equal to
Experiments with cathode rays led to the discovery of the...
electron
Whose series of experiments identified the nucleus of the atom?...
Rutherford
Because most particles fired at metal foil passed straight through, Rutherford concluded that...
atoms were mostly empty space
The atomic number of oxygen, 8, indicates that there are eight...
protons in the nucleus of an oxygen atom.
The total number of protons and neutrons in the nucleus of an atom is its...
mass number
Chloride has atomic number 17 and mass number 35. It has...
17 protons, 17 electrons, and 18 neutrons
The mass of 1 mol of chromium (atomic mass 51.996 amu) is...
51.996 g
How many moles of atoms are in 50.15 g of mercury (atomic mass 200.59 amu)?...
0.2500 mol
A sample of tin (atomic mass118.71 amu) contains 3.01 x 1023 atoms. The mass of the sample is...
59.3 g
The mass of 5.000 mol of cesium (atomic mass 132.9 amu) is...
664.5 g
For electromagnetic radiation, c (the speed of light) equals...
frequency times wavelength
A quantum of electromagnetic energy is called a...
photon
The specific wavelengths of light seen through a prism that are made when high-voltage current is passed through a tube of hydrogen gas at low pressure is a...
line-emission spectrum
If electrons in an atom have the lowest possible energies, the atom is in the...
ground state
The Bohr model of the atom is an attempt to explain hydrogen's _______...
line-emission spectrum
According to the Bohr model of the atom, the single electron of a hydrogen atom circles the nucleus...
in specific, allowed orbits
Which model of the atom explains the orbitals of electrons as waves?...
the quantum model
All of the following describe the Heisenberg uncertainly principle except...
it helps to locate an electron in an atom
A three-dimensional region around a nucleus where an electron may be found is called an...
orbital
The main energy levels of an atom are indicated by the...
principal quantum numbers
The angular momentum quantum number indicates the...
shape of an orbital
How many orbitals can exist at the third main energy level?...
9
How many electrons are needed to completely fill the fourth energy level?...
32
The statement that an electron occupies the lowest available energy orbital is...
the Aufbau principle
The element with electron configuration 1s2 2s2 2p6 3s2 3p2 is...
Si (Z=14)
What is the electron configuration for nitrogen, atomic number 7?...
1s^2 2s^2 2p^3
The number of electrons in the highest energy level of the argon atom (atomic number 18) is...
8
The electrons involved in the formation of a chemical bond are called...
valence electrons
The B―F bond in BF3 (electronegativity for B is 2.0; electronegativity for F is 4.0) is...
ionic
Bond length is the average distance between two bonded atoms...
at which potential energy is at a minimum
In drawing a Lewis structure, each nonmetal atom except hydrogen should be surrounded by...
8 electrons
In drawing a Lewis structure, the central atom is generally the...
least electronegative atom
62. What is the correct Lewis structure for hydrogen chloride, HCl?
..
H-Cl..
..
Bonding in molecules or ions that cannot be correctly represented by a single Lewis structure is...
resonance
VSEPR theory is a model for predicting...
the shape of molecules
According to VSEPR theory, the structure of the ammonia molecule, NH3,
is...
trigonal-pyramidal
Use VSEPR theory to predict the shape of the hydrogen chloride molecule, HCl...
linear
Use VSEPR theory to predict the shape of the carbon tetraiodide molecule, Cl4...
tetrahedral
Dipole-dipole forces are considered the most important forces in polar substances because the London dispersion forces present in polar substances...
are usually much weaker than the dipole-dipole forces
The strength of London dispersion forces between molecules depends on...
both the number of electrons in the molecule and the mass of the molecule
Give the name: NaCl
Sodium Chloride
P3S5
Triphosphorus Pentasulfide
(NH4)3N
Ammonium Nitride
CO
Carbon Monoxide
FeSO4
Iron (II) Sulfate
Give the formula: Dinitrogen heptabromide
N2Br7
Magnesium Phosphate
Mg3 (PO4)2
Iron (III) Iodide
FeI3
Potassium Nitride
K3N
Lead (IV) Oxide
PbO2