Which one of the following statements concerning matter is correct?
a) a gas has a fixed volume but not a rigid shape
b) a liquid has a fixed volume and a rigid shape
c) a liquid takes on both the volume and the shape of its container
d) a solid has a fixed volume and a rigid shape
e) both b and d are correct
d
All of the following statements are true EXCEPT
a) of the 113 known elements, 91 occur naturally
b) an element cannot be broken down into two or more pure substances
c) a compound is a substance that contains two or more elements
d) a pure compound always contains the same elements in the same mass percentages
e) another name for a heterogeneous mixture is a solution
e
Which term best describes table salt (NaCl) at room temperature?
a) gas
b) element
c) compound
d) homogeneous mixture
e) heterogeneous mixture
c
All of the following statements are false EXCEPT
a) copper (Cu) is a homogeneous mixture of carbon (C) and uranium (U)
b) table salt is a heterogeneous mixture of sodium metal and chlorine gas
c) soda water is a homogeneous mixture of carbon dioxide gas and water
d) sugar dissolves completely in water to give a heterogeneous mixture
e) water (H20) is a homogeneous mixture containing hydrogen and oxygen
c
All of the following statements are true EXCEPT
a) potassium is represented by the symbol K
b) zinc is represented by the symbol Zn
c) argon is represented by the symbol Ar
d) iron is represented by the symbol Fe
e) nitrogen is represented by the symbol Ni
e
Which method is best for removing the pulp from orange juice?
a) distillation
b) light absorption
c) electrolysis
d) gas-liquid chromatography
e) filtration
e
Vinegar is a homogeneous mixture of two liquids: acetic acid and water. Which method is best for separating the components of vinegar?
a) distillation
b) filtration
c) electrolysis
d) gas-liquid chromatography
e) light absorption
a
The gravity on the surface of Earth is 6.02 times greater than that on the moon. If an object has both a mass and weight of 1.00 kg on earth, on the moon the same object will have
a) a mass of 1.00 kg and a weight of 0.166 kg
b) a mass of 1.00 kg and a weight of 1.00 kg
c) a mass of 1.00 kg and a weight of 6.02 kg
d) a mass of 0.166 kg and a weight of 0.166 kg
e) a mass of 0.166 kg and a weight of 1.00 kg
a
What is a correct method for converting Celsius to kelvin?
a) t(K)=9K/5C (tC-273.15C)
b) t(K)=5K/9C (tC+273.15C)
c) t(K)=1K/1C (tC-273.15C)
d) t(K)=1K/1C (tC+273.15C)
e) none of the above
d
If the outdoor temperature is 17.0 degrees Celsius, what is the temperature in Fahrenheit?
a) -1.40 degrees Fahrenheit
b) 30.6 degrees Fahrenheit
c) 41.4 degrees Fahrenheit
d) 62.6 degrees Fahrenheit
e) 74.6 degrees Fahrenheit
d
Which is a correct expression for converting Celsius to Fahrenheit?
a) degrees Fahrenheit=(5F/9C) tC-32F
b) degrees Fahrenheit=(5F/9C) tC+32F
c) degrees Fahrenheit=(5F/9C) (tC+32F)
d) degrees Fahrenheit=(9F/5C) tC-32F
e) degrees Fahrenheit=(9F/5C) tC+32F
e
Many experiments are conducted at 298 K. What is this temperature in Celsius?
a) 0 C
b) 25 C
c) 55 C
d) 273 C
e) 298 C
b
Express 4.220 x 10^2 mL in standard notation.
a) 0.0422 mL
b) 0.04220 mL
c) 422 mL
d) 422.0 mL
e) 4220 mL
d
What is the correct answer to the expression below?
2.54cm/inch x (182.3 inch - 179.219 inch)
a) 8 cm
b) 7.8 cm
c) 7.83 cm
d) 7.826 cm
e) 7.8257 cm
b
All of the following are exact conversions EXCEPT
a) 1 pound=453.6 g
b) 1 m^3=1x10^3 L
c) 1 cm^3=1 mL
d) 2.54 cm=1 inch
e) 1 kg=1x10^3 g
a
All of the following are examples of chemical change EXCEPT
a) the fermentation of wine
b) the tarnishing of silver
c) the condensation of steam
d) the combustion of butane gas
e) the rusting of iron
c
An intensive property is
a) too small to be observed
b) dependent only on mass and temperature
c) visible to the human eye
d) dependent upon amount
e) independent of amount
e
An aqueous solution of copper sulfate is blue. This solution absorbs
a) blue light
b) red light
c) only infrared light
d) only ultraviolet light
e) only light with wavelengths shorter than 400 nm
b
Which description most accurately describes neptunium-239?
a) mass number=93, atomic number=239
b) mass number=93, number of neutrons=146
c) mass number=146, atomic number=93
d) number of protons=93, number of neutrons=146
e) number of protons=93, atomic number=239
d
Which two atoms below have the same number of neutrons?
(top:15, bottom:8) O,
(top:16, bottom:8) O,
(top:20, bottom:9) F,
(top:20, bottom:10) Ne,
(top:22, bottom:11) Na
a) (top:15, bottom:8) O and (top:16, bottom:8) O
b) (top:16, bottom:8) O and (top:22, bottom:11) Na
c) (top:20, bottom:9) F and (top:22, bottom:11) Na
d) (top:20, bottom:9) F and (top:22, bottom:11) Na
e) (top:20, bottom:10) Ne and (top:22, bottom:11) Na
d
Which two of the ions below have the same number of electrons?
(top:127, bottom:53) I^1-,
(top:119, bottom:50) Sn^2+,
(top:207, bottom:82) Pb^2+
(top:207, bottom:82) Pb^4+
(top:137, bottom:56) Ba^2+
a) (top:127, bottom:53) I^1- and (top:137, bottom:56) Ba^2+
b) (top:127, bottom:53) I^1- and
c) top:207, bottom:82) Pb^2+ and (top:137, bottom:56) Ba^2+
d) (top:119, bottom:50) Sn^2+ and (top:137, bottom:56) Ba^2+
e) top:207, bottom:82) Pb^2+ and (top:207, bottom:82) Pb^4+
a
Which species has 63 neutrons?
a) (top:112, bottom:48) Cd
b) (top:112, bottom:49) In
c) (top:63, bottom:29) Zn
d) (top:152, bottom:63) Eu
e) none of the above
b
What is the identity of (top:55, bottom:25) X?
a) zinc
b) silver
c) iridium
d) cesium
e) manganese
e
Beta particles have identical properties to
a) helium atoms that have been stripped of their electrons
b) elemental helium
c) high energy radiation
d) neutrons
e) electrons
e
How many protons and electrons are in a sulfate ion, SO4^2-?
a) 46 protons and 48 electrons
b) 48 protons and 48 electrons
c) 48 protons and 50 electrons
d) 50 protons and 48 electrons
e) none of the above
c
All of the following groups are considered main group elements EXCEPT
a) group 2
b) group 7
c) group 14
d) group 17
e) group 18
b
Which group of three elements contains a transition metal, a halogen, and a noble gas?
a) S, I, Cu
b) Br, Kr, Ba
c) Ar, Hg, Rn
d) Ce, N, He
e) Cu, I, Xe
e
How many nonmetals, metalloids, and metals are in group 14?
a) 0 nonmetals, 3 metalloids, and 2 metals
b) 1 nonmetals, 2 metalloids, and 2 metals
c) 2 nonmetals, 2 metalloids, and 1 metals
d) 2 nonmetals, 1 metalloids, and 2 metals
e) 3 nonmetals, 0 metalloids, and 2 metals
b
Identify the ions and their charges in Na2SO4.
a) Na^+, SO4^-
b) Na^+, SO4^2-
c) Na^+, SO^4-
d) Na^2+, SO^4-
e) Na^2+, SO4^2-
b
Identify the ions and their charges in Mg3N2
a) Mg^+, N^3-
b) Mg^2+, N^3-
c) Mg^3+, N^2-
d) Mg3^2+, N2^3-
e) Mg3^6+, N2^6-
b
What are the values for x and y, respectively, in CaxHyPO4?
a) 1 and 2
b) 2 and 1
c) 1 and 3
d) 2 and 2
e) 1 and 1
e
What is the correct name for Ag2O?
a) silver (I) oxide
b) silver (I) monoxide
c) silver (II) oxide
d) silver dioxide
e) disilver monoxide
a
What is the correct formula for chromium (II) nitrate?
a) Cr3NO3
b) Cr(NO3)3
c) Cr2(NO3)3
d) Cr3(NO3)2
e) Cr3(NO3)3
b
What is the correct name for N203?
a) nitrogen oxide
b) nitrogen (II) oxide
c) nitrogen (III) oxide
d) trioxygen dinitride
e) dinitrogen trioxide
e
What is the correct name for PF5?
a) phosphorous pentafluoride
b) phosphorous (V) fluoride
c) phosphorofluoride
d) pentafluorophosphorus
e) pentafluorophosphate
a
What is the correct formula for potassium dichromate?
a) K2Cr2O7
b) K2(Cr2O7)2
c) K2CrO4
d) (K2CrO4)2
e) KCrO4
a
What is the correct name for HI (aq)?
a) hydroiodic acid
b) hydrogen iodide ion
c) monohydrogen monoiodide
d) iodate acid
e) iodine hydride
a
Gallium has an atomic mass of 69.7 amu. In a typical sample, 60.4% of Ga exists as Ga-69 (68.9257 amu). What is the identity and the atomic mass of the other isotope?
a) (top:70, bottom:30) Ga; 70.9 amu
b) (top:70, bottom:31) Ga; 70.9 amu
c) (top:71, bottom:31) Ga; 70.9 amu
d) (top:71, bottom:31) Ga; 71.9 amu
e) (top:72, bottom:31) Ga; 71.9 amu
c
An element has three naturally occurring isotopes with the following abundances and masses:
abundance: 78.99%, mass (amu): 23.985042
abundance: 10.00%, mass (amu): 24.985837
abundance: 11.01%, mass (amu): 25.982593
Determine the atomic mass of the element
a) 24.31
b) 24.98
c) 74.95
d) 2431
e) none of the above
a
The average molar mass of lithium is 6.941. A sample of lithium consists of two isotopes with masses of 6.01512 amu and 7.01600 amu. Determine the percent abundance of each isotope.
a) 74.9% Li-6 and 92.51% Li-7
b) 8.45% Li-6 and 91.55% Li-7
c) 12.49% Li-6 and 87.51% Li-7
d) 91.55% Li-6 and 8.45% Li-7
e) 92.51% Li-6 and 7.49% Li-7
a
The mass of a single atom of ziroconium is 1.515x10^-22 grams. Which is a correct method for determining the molar mass of Zr.
a) (1 g/1.515x10^-22 atoms)(1 atom/6.022x10^23 moles)
b) (1 g/1.515x10^-22 atoms)(6.022x10^23 atoms/1 mole)
c) (1.515x10^-22 g/1 atom)(1 atom/6.022x10^23 moles)
d) (1.515x10^-22 g/1 atom)(6.022x10^23 atoms/1 mole)
e) none of the above
d
The mass of a single atom of sulfur is 5.325x10^-23 grams. Which is a correct method for determining molar mass of elemental sulfur, S8?
a) (5.325x10^-23 g S/1 atom)(1 atom/6.022x10^23 moles)(1 mole S8/ 8 mole S)
b) (5.325x10^-23 g S/1 atom)(6.022x10^23 atoms/1 mole S)(8 mole S/1 mole S8)
c) (5.325x10^-23 g S/1 atom)(1 atom/6.022x10^23 moles)(8 mole S/1 mole S8)
d) (1 atom/5.325x10^-23 g S)(6.022x10^23 moles/1 atom)(1 mole S8/ 8 mole S)
e) (5.325x10^-23 g S/1 atom)(6.022x10^23 atoms/1mole S)(1 mole S8/ 8 mole S)
b
A 1.45 g sample of chromium contains _____ atoms.
a) 1.25x10^22
b) 1.6x10^22
c) 8.73x10^23
d) 2.16x10^25
e) 4.54x10^25
b
You have a 5.0 g sample of each of the following elements: Ra, Rb, Rh, Rn, Ru. Which sample contains the most atoms?
a) Ra
b) Rb
c) Rh
d) Rn
e) Ru
b
Which of the following samples contains the largest number of atoms?
a) 2.0 moles of H3PO4
b) 3.0 moles of H2SO3
c) 4.0 moles of HNO3
d) 6.0 moles of HClO
e) 8.0 moles of HBr
c
Which of the following samples contains the largest number of hydrogen atoms?
a) 2.0 moles of C6H16
b) 3.0 moles of C3H8
c) 4.0 moles of C3H6
d) 6.0 moles of C2H4
e) 8.0 moles of C2H2
a
What is the mass in grams of 0.362 moles nitric acid (HNO3)?
a) 0.00574 g
b) 0.0438 g
c) 22.8 g
d) 53.8 g
e) 174 g
c
What is the percent composition of silicon nitride (Si3N4)?
a) 30.21% Si and 69.79% N
b) 42.92% Si and 57.08% N
c) 54.03% Si and 45.97% N
d) 60.06% Si and 39.94% N
e) 69.40% Si and 30.60% N
d
What is the percent composition of iron (II) sulfate hexahydrate?
a) 4.2% Fe; 4.2% S; 41.6% O; 50.0% H
b) 16.7% Fe; 16.7% S; 66.6% O
c) 21.5% Fe; 12.3% S; 24.6% O; 41.6% H
d) 21.5% Fe; 12.3% S; 61.5% O; 4.7% H
e) 36.8% Fe; 21.1% S; 42.1% O
d
Isopentyl acetate, a molecule composed of C, H, and O, smells like bananas. Combustion analysis of 1.750 grams of this molecule yields 1.695 g H2O and 4.142 g CO2. What is the simplest formula for isopentyl acetate?
a) C7H14O2
b) C7H7O4
c) C8H10O3
d) C8H16O
e) C9H6O
a
The catalytic conversion of ammonia to nitric oxide is the first step in a three-step process which ultimately results in nitric acid. Balance the equation for the reaction.
aNH3(g) + bO2(g) -> cNO(g) + dH2O(g)
a) a=2, b=1, c=2, d=1
b) a=3, b=2, c=3, d=3
c) a=4, b=3, c=2, d=6
d) a=4, b=5, c=4, d=6
e) a=6, b=15, c=6, d=9
d
The combustion of methanol, CH3OH, yields carbon dioxide and water as products. Which of the reactions below is correct and properly balanced?
a) CH3OH(l) + O2(g) -> CO2(g) + H2O(g)
b) CH3OH(l) + O2(g) -> CO2(g) + 2H2O(g)
c) 2CH3OH(l) + O2(g) -> 2CO2(g) + 4H2O(g)
d) 2CH3OH(l) + 2O2(g) -> 2CO2(g) + 2H2O(g)
e) 2CH3OH(l) + 3O2(g) -> 2CO2(g) + 4H2O(g)
e
Aluminum reacts with oxygen to form aluminum oxide. Which of the reactions below is correct and properly balanced?
a) Al(s) + O(g) -> AlO(s)
b) 2Al(s) + O(g) -> 2AlO(s)
c) 3Al(s) + O(g) -> Al3O2(s)
d) 4Al(s) + O(g) -> 2Al2O(s)
e) 4Al(s) + 3O(g) -> 2Al2O3(s)
e
If 16.4 g of oxygen gas react with excess hydrogen, what mass of water is produced?
2H2(g) + O2(g) -> 2H2O(g)
a) 9.23 g
b) 18.5 g
c) 20.4 g
d) 23.9 g
e) 36.9 g
b
Which method is correct for determining the mass of carbon dioxide that can be made by the combustion of 3.219 grams of ethanol with excess oxygen?
C2H5OH(l) + 3O2(g) -> 2CO2(g) + 3H2O(l)
a) 3.219 g C2H5OH (1 mole/46.07g)(2 mole CO2/1 mole C2H5OH)(44.01g CO2/1 mole)
b) 3.219 g C2H5OH (1 mole/46.07g)(1 mole CO2/2 mole C2H5OH)(44.01g CO2/1 mole)
c) 3.219 g C2H5OH (1 mole/46.07g)(1 mole CO2/1 mole C2H5OH)(44.01g CO2/1 mole)
d) 3.219 g C2H5OH (46.07 mole/1g)(2 mole CO2/1 mole C2H5OH)(44.01g CO2/1 mole)
e) 3.219 g C2H5OH (46.07 mole/1g)(1 mole CO2/2 mole C2H5OH)(44.01g CO2/1 mole)
a
How many moles of ammonia can be made by reacting 7.0 moles of N2 with 4.0 moles of H2?
N2(g) + 3H2(g) -> 2NH3(g)
a) 2.7 mol
b) 4.0 mol
c) 7.0 mol
d) 11 mol
e) 14 mol
a
What mass of oxygen will react with 2.64 g of magnesium?
2Mg(s) + O2(g) -> MgO(s)
a) 0.487 g
b) 1.00 g
c) 1.26 g
d) 1.74 g
e) 3.47 g
d
A mass of 8.15 g C2H4(g) reacts with excess oxygen. If 16.2 g CO2(g) is collected, what is the percent yield of the reaction?
C2H4(g) + 3O2(g) -> 2CO2(g) + 2H2O(g)
a) 25.6%
b) 31.7%
c) 41.0%
d) 57.1%
e) 63.3%
e
2.500 grams of MgSO4xH2O, a hydrated salt with an unknown water content, is dried in an oven to remove the water. After drying, the anhydrous salt has a mass of 1.221 grams. How many moles of water are present per mole of hydrated magnesium sulfate?
a) 1
b) 3
c) 5
d) 7
e) 9
d
Which of the following methods correctly describes the preparation of 1.00L of an aqueous solution of 0.500 M NaOH?
a) place 0.500 g NaOH(s) in a flask and dilute to 1.00 L with water
b) place 0.500 g NaOH(s) in a flask and add 1.00 L of water
c) place 20.0 g NaOH(s) in a flask and dilute to 1.00 L with water
d) place 20.0 g NaOH(s) in a flask and add 1.00 L of water
e) place 40.0 g NaOH(s) in a flask and add 500 g of water
c
If 17 g MgCl2 is dissolved in 5.0 L of water, what is the chloride ion molarity in the solution?
a) 0.036 M
b) 0.071 M
c) 0.68 M
d) 0.77 M
e) 7.8 M
b
Which of the following methods is correct for calculating the moles of Al^3+ in 125 mL of 0.234 M Al(NO3)3?
a) (0.234 mol Al(NO3)3/125 mL)(1000 mL/1 L)(1 mol Al^3+/1 mol Al(NO3)3)
b) (0.234 mol Al(NO3)3/125 mL)(1000 mL/1 L)(1 mol Al^3+/3 mol Al(NO3)3)
c) 125 mL(1 L/1000 mL)(0.234 mol Al(NO3)3/1 L)(1 mol Al^3+/3 mol Al(NO3)3)
d) 125 mL(1000 mL/1 L)(1 L/0.234 mol Al(NO3)3)(1 mol Al^3+/1 mol Al(NO3)3)
e) 125 mL(1 L/1000 mL)(0.234 mol Al(NO3)3/1 L)(1 mol Al^3+/1 mol Al(NO3)3)
e
A mass of 12.0 g of calcium chloride is diluted to a volume of 250 mL in a volumetric flask. Which of the equations below is a correct method for determining the chloride ion concentration?
a) (12.0g CaCl2/250 mL)(1000mL/1 L)(1 mole CaCl2/111.0 g)
b) (12.0g CaCl2/250 mL)(1L/1000mL)(1 mole CaCl2/111.0 g)(2 mole Cl-/1 mole CaCl2)
c) (12.0g CaCl2/250 mL)(1000mL/1L)(1 mole CaCl2/111.0 g)(2 mole Cl-/1 mole CaCl2)
d) (12.0g CaCl2/250 mL)(1L/1000mL)(1 mole CaCl2/111.0 g)(1 mole CaCl2/2 mole Cl-)
e) (12.0g CaCl2/250 mL)(1000mL/1L)(1 mole CaCl2/111.0 g)(1 mole CaCl2/2 mole Cl-)
c
What mass of potassium ions is present in 25.0 mL of 0.50 M K2SO4?
a) 0.250 g
b) 0489 g
c) 0.978 g
d) 2.18 g
e) 4.36 g
c
Which of the following ionic compounds are likely to be soluble in water: Mg(OH)2, Pb(NO3)2, AgI, Na2CO3, and Cu3(PO4)3?
a) Na2CO3 only
b) Pb(NO3)2 and Na2CO3
c) Mg(OH)2, Na2CO3, and Cu3(PO4)3
d) Mg(OH)2, AgI ,and Cu3(PO4)3
e) Pb(NO3)2, AgI, Na2CO3, and Cu3(PO4)3
b
What reaction occurs when aqueous solutions of magnesium nitrate and potassium iodide are mixed?
a) Mg^2+(aq) + 2K^+(aq) -> MgK2(s)
b) Mg^2+(aq) + 2I^-(aq) -> MgI2(s)
c) NO3^-(aq) + K^+(aq) -> KNO3(s)
d) Mg^2+(aq) + 2 NO3^-(aq) + 2K^+(aq) + 2I^-(aq) -> MgI2(s) + 2KNO3(s)
e) no reaction occurs
e
Write a balanced net ionic equation for the reaction of aluminum hydroxide, Al(OH)3, with nitric acid.
a) Al(OH)3(s) + 3H^+(aq) -> Al^3+(aq) + 3H2O
b) Al(OH)3(s) + 3H^+(aq) -> AlH3(s) + 3OH^-(aq)
c) (OH)3(aq) + 3H^+(aq) -> 3H2O
d) 3OH^-(aq) + 3H^+(aq) -> 3H2O
e) Al^3+(aq) + 3NO3^-(aq) -> Al(NO3)3(aq)
a
Write a balanced net ionic equation for the reaction of aqueous solutions of lead (II) nitrate and potassium chloride.
a) Pb(NO3)2(aq) + 2KCl(aq) -> PbCl2(s) + 2 KNO3(aq)
b) Pb^2+(aq) + 2K^+(aq) -> PbK2(s)
c) Pb^2+(aq) + 2Cl^-(aq) -> PbCl2(s)
d) NO3^-(aq) + K^+(aq) -> KNO3(s)
e) no precipitation occurs
c
Identify all of the spectator ions in the precipitation reaction below.
Ca^2+(aq) + 2Br^-(aq) + 2Li^+(aq) + CO3^2-(aq) -> CaCO3(s) + 2Li^+(aq) + 2Br^-(aq)
a) Ca^2+ and Li^+
b) Br^- and CO3^2-
c) Br^- and Li^+
d) CaCO3
e) Ca^2+, Br^-, Li^+, and CO3^2-
c
According to the Arrhenius acid-base definition
a) acids produce H^+ in aqueous solutions and bases produce OH^- in aqueous solutions
b) acids produce OH^- in aqueous solutions and bases produce H^+ in aqueous solutions
c) acids only react with bases
d) all hydrogen halides are strong acids
e) acids and bases are strong electrolytes
a
Which list contains only strong acids?
a) HCl, HNO3, HF, HClO4
b) H2SO4, H3PO4, HClO4, NH3
c) HCl, HNO3, H3PO4, HClO4
d) HCl, H2SO4, HClO4, HI
e) HNO3, H2SO4, NaOH, H3PO4
d
NH3(aq) is a
a) strong base
b) strong acid
c) weak base
d) weak acid
e) neither an acid nor a base
c
What is the balanced net ionic equation for the reaction between aqueous solutions of acetic acid and sodium hydroxide?
a) CH3CO2H(aq) + OH^-(aq) -> CH3(aq) + CO3^2-(aq) + H2(aq)
b) CH3CO2H(aq) + 3NaOH(aq) -> CCO2H^3-(aq) + 3Na^+(aq) + H2O
c) CH3CO2H(aq) + OH^-(aq) -> CH3^-(aq) + CO2(g) + H2O
d) CH3CO2H(aq) + OH^-(aq) -> CH3CO2^-(aq) + H2O
e) CH3CO2H(aq) + 2Na^+(aq) + 2OH^-(aq) -> CH3CO2^2-(aq) + 2Na^+(aq) + H2O
d
When HCl(g) and NH3(g) are mixed, a white solid forms. What is the balanced equation for this reaction?
a) HCl(g) + NH3(g) -> NH4Cl(s)
b) HCl(g) + NH3(g) -> NH2Cl(g) + H2(s)
c) HCl(g) + NH3(g) -> NH4(s) + Cl(g)
d) HCl(g) + NH3(g) -> NH2Cl(s) + H2(g)
e) 3HCl(g) + NH3(g) -> NCl3(s) + 3H2(g)
a
What is the balanced net ionic equation for the neutralization of aqueous solutions of sodium hydroxide and perchloric acid, HClO4?
a) OH^-(aq) + HClO4(aq) -> H2O + ClO4^-(aq)
b) NaOH(aq) + H^+(aq) -> H2O + Na^+(aq)
c) Na^+(aq) + ClO4^-(aq) -> NaClO4(s)
d) OH^-(aq) + H^+(aq) ->H2O
e) None of the above are correct
d
In the laboratory, acid spills are often neutralized by adding sodium bicarbonate. What mass of sodium bicarbonate reacts with 225 mL of 6.00 M HCl?
H^+(aq) + NaHCO3(s) -> H2O + CO2(g) + Na^+(aq)
a) 1.35 g
b) 71.5 g
c) 113 g
d) 143 g
e) 2240 g
c
A 25.00 mL sample of vinegar is diluted with water to a final volume of 250.0 mL. A 25.00 mL portion of the diluted vinegar is then titrated with 0.0998 M NaOH. If 22.43 mL of NaOH is required to reach the equivalence point, what is the original concentration of acetic acid in the vinegar?
CH3CO2H(aq) + OH^-(aq) -> CH3CO2^-(aq) + H2O
a) 0.0538 M
b) 0.0895 M
c) 0.538 M
d) 0.895 M
e) 5.38 M
d
The principle ingredient in Tums antacid tablets is calcium carbonate, CaCO3. A single tablet contains 0.500 g CaCO3. What volume of 0.2500 M HCl is required to titrate a tablet of Tums?
2H^+(aq) + CO3^2-(aq) -> H2O + CO2(g)
a) 0.0100 mL
b) 0.0200 mL
c) 10.0 mL
d) 20.0 mL
e) 40.0 mL
e
A reducing agent is a species that
a) takes a proton from an Arrhenius acid
b) is reduced in a chemical reaction
c) gains electrons in a chemical reaction
d) loses electrons in a chemical reaction
e) gives a proton to an Arrhenius base
d
Assign oxidation numbers to each atom in calcium perchlorate, Ca(ClO4)2.
a) Ca=0; Cl=0; O=0
b) Ca=0; Cl=-1; O=-2
c) Ca=+2; Cl=-1; O=-2
d) Ca=+2; Cl=+5; O=-2
e) Ca=+2; Cl=+7; O=-2
e
Assign oxidation numbers to each atom in manganese(IV) oxide.
a) Mn=+4;O=0
b) Mn=+4;O=-2
c) Mn=+2;O=0
d) Mn=+2;O=-2
e) Mn=0;O=0
b
What is the reduction half-reaction for the equation below?
5Fe^2+(aq) + MnO4^-(aq) + 8H^+(aq) -> 5Fe^3+(aq) + Mn^2+(aq) + 4H2O
a) MnO4^-(aq) + 5e^- -> Mn^2+(aq) + 2O2(g)
b) MnO4^-(aq) + 8 H^+(aq) +5e^- -> Mn^2+(aq) + 4H2O
c) Fe^2+(aq) + e^- -> Fe^3+(aq)
d) 8H^+(aq) + 8e^- -> 8H2O
e) none of the above
b
Identify the reaction type for the reaction between potassium metal and hydrochloric acid.
2K(s) + 2H^+(aq) -> 2K^+(aq) + H2(g)
a) precipitation
b) acid-base
c) oxidation-reduction
d) both a and c
e) none of the above
c
If the volume of a confined gas is doubled at constant temperature, what change is observed?
a) the pressure of the gas is decreased to 1/4 of its original value
b) the pressure of the gas is decreased to 1/2 of its original value
c) the pressure of the gas is increased to twice its original value
d) the density of the gas is doubled
e) the velocities of the molecules are doubled
b
Place the following units of pressure in order from lowest to highest pressure
a) 1 atm<1 Pa<1 mm Hg<1 bar
b) 1 mm Hg<1 bar<1 atm<1 Pa
c) 1 Pa<1 mm Hg<1 bar<1 atm
d) 1 Pa<1 mm Hg<1 atm<1 bar
e) 1 bar<1 mm Hg<1 Pa<1 atm
c
Avogadro's law states that
a) 1 liter of any gas contains 6.02 x 10^23 gas molecules
b) the volume of a gas is directly proportional to its temperature
c) the gas constant equals 0.0821 L x atm/(mol x K) for all gases
d) the volume of a gas must always be constant
e) equal volumes of all gases at the same pressure and temperature contain an equal number of moles
e
The molar mass of helium and oxygen are 4.0g/mol and 16g/mol, respectively. At the same temperature and pressure, 1 mole of helium will occupy
a) the same volume as 1 mole of oxygen
b) four times the volume of 1 mole of oxygen
c) twice the volume of 1 mole of oxygen
d) half the volume of 1 mole of oxygen
e) one fourth the volume of 1 mole of oxygen
a
A bicycle tire is filled to a pressure of 4.42 atm (65 psi) at a temperature of 12 degrees Celsius. If the temperature increases to 33 degrees Celsius, what is the pressure in the tire? Assume the volume of the tire is constant.
a) 4.75 atm
b) 5.91 atm
c) 9.28 atm
d) 12.1 atm
e) 16.1 atm
a
At 108 degrees Celsius, the pressure in a 10.0 L flask is 874 mm Hg. How many moles of gas are in the flask?
a) 0.368 mol
b) 0.873 mol
c) 1.30 mol
d) 348 mol
e) 986 mol
a
A 3.00 L flask contains 2.33 g of argon gas at 312 mm Hg. What is the temperature of the gas?
a) 151 K
b) 257 K
c) 292 K
d) 341 K
e) 4890 K
b
A mass of 5.0 grams of dry ice, CO2(s), is sealed in an evacuated 2.0 L plastic soda bottle. What is the pressure inside the bottle when the CO2 is heated to 35 degrees Celsius?
a) 0.16 atm
b) 1.4 atm
c) 8.9 atm
d) 18 atm
e) 63 atm
b
25.0 L of hydrogen gas at 50.0 atm and 25 degrees Celsius expands to 65.0 L and is subsequently heated to 35 degrees Celsius. What is the new pressure?
a) 19.9 atm
b) 25.2 atm
c) 26.9 atm
d) 28.4 atm
e) 31.2 atm
a
What volume of oxygen (O2) at 22 degrees Celsius and 1.00 atm contains the same number of molecules as 0.400 L H2 at 45 degrees Celsius and 1.00 atm?
a) 0.251 L
b) 0.298 L
c) 0.371 L
d) 0.400 L
e) 0.431 L
c
A volatile compound with a mass of 0.8822 grams is placed in an evacuated 0.250 L flask. The flask is heated to evaporate the compound. At 99 degrees Celsius, the pressure in the flask is 1.25 atm. What is the molar mass of the compound?
a) 86.2 g/mol
b) 116 g/mol
c) 229 g/mol
d) 257 g/mol
e) 303 g/mol
a
What is the density of argon gas at 25 degrees Celsius and 1.00 atm?
a) 0.0110 g/L
b) 1.63 g/L
c) 19.5 g/L
d) 977 g/L
e) 1.24 x 10^3 g/L
b
At 1.00 km above sea level, the atmospheric pressure is 675 mm Hg and the temperature is 282 K. If nitrogen comprises 78.1% (mole percent) of air, what is the density of nitrogen at this height?
a) 0.0238 g/L
b) 0.521 g/L
c) 0.839 g/L
d) 1.07 g/L
e) 638 g/L
c
A mass of 0.650 grams of calcium carbonate is added to 50.0 mL of 0.275 M HCl. If the CO2(g) gas is collected in a 1.00 L flask at 25 degrees Celsius, what is the pressure of CO2(g) in the flask?
CaCO3(s) + 2H^+(aq) -> Ca^2+(aq) + H2O(l) + CO2(g)
a) 0.0129 atm
b) 0.0583 atm
c) 0.159 atm
d) 0.314 atm
e) 15.9 atm
c
The composition (in mole percent) of the atmosphere is 78.1% N2, 21.0% O2, and 0.9% Ar. What is the partial pressure of each gas when the barometric pressure is 754.1 mm Hg
a) N2=21.1 atm, O2=6.5 atm, Ar=0.3 atm
b) N2=78.1 mm Hg, O2=21.0 mm Hg, Ar=0.9 mm Hg
c) N2=244 mm Hg, O2=244 mm Hg, Ar=244 mm Hg
d) N2=405 mm Hg, O2=234 mm Hg, Ar= 293 mm Hg
e) N2=589 mm Hg, O2=158 mm Hg, Ar=7 mm Hg
e
Sulfur burns in oxygen with a deep blue flame to produce sulfur dioxide. If 5.85 g S8 and 1.00 atm of O2 completely react in a 5.00 L flask at 25 degrees Celsius, determine the partial pressure of SO2 and the total pressure in the flask.
S8(s) + 8O2(g) -> 8SO2(g)
a) O2=0 atm , SO2=1.00 atm ,total pressure=1.00 atm
b) O2=0.093 atm , SO2=0.917 atm ,total pressure=1.00 atm
c) O2=0.107 atm , SO2=0.893 atm ,total pressure=1.00 atm
d) O2=0.855 atm , SO2=0.145 atm ,total pressure=1.00 atm
e) O2=0.917 atm , SO2=0.163 atm ,total pressure=1.08 atm
c
An unknown mass of ammonium perchlorate, NH4ClO4 (117.5 g/mol), is placed in an evacuated 1.00 L flask and heated to 251 degrees Celsius. At this temperature the NH4ClO4 decomposes violently. The gaseous products exert a pressure of 466 mm Hg at 251 degrees Celsius. What mass of NH4ClO4 was placed in the flask?
2NH4ClO4(s) -> N2(g) + Cl2(g) + 2O2(g) + 4H2O(g)
a) 0.149 g
b) 0.419 g
c) 0.682 g
d) 1.67 g
e) 3.19 g
b
Water can be decomposed by electrolysis to hydrogen gas and oxygen gas. What mass of water must decompose to yield 24.0 L of oxygen gas at 1.00 atm and 25 degrees Celsius?
2H2O(l) -> 2H2(g) + O2(g)
a) 11.1 g
b) 17.7 g
c) 23.6 g
d) 35.3 g
e) 70.7 g
d
A mixture of methane and helium is placed in a 2.0 L flask at 27 degrees Celsius. The partial pressure of CH4 is 0.72 atm and the partial pressure of helium is 0.22 atm. What is the mole fraction of methane?
a) 0.23
b) 0.29
c) 0.50
d) 0.77
e) 3.5
d
All of the following are properties of gases according to the kinetic theory EXCEPT
a) gases consist of mostly empty space
b) attractive forces cause gas molecules to collide
c) gas pressure is caused by collisions of molecules with the container walls
d) collisions between gas molecules are elastic
e) gas molecules are in constant motion
b
The average kinetic energy of a gas molecule is
a) directly proportional to its average speed
b) directly proportional to the square of its mass
c) directly proportional to the square of its average speed
d) inversely proportional to its average speed
e) inversely proportional to the square of its mass
c
If a gas effuses 1.73 times faster than Kr, what is its molar mass?
a) 16.0 g/mol
b) 28.0 g/mol
c) 36.6 g/mol
d) 55.4 g/mol
e) 126.9 g/mol
b
In an experiment, argon is allowed to effuse through a tiny opening into an evacuated 5.00 x 10^2 mL flask for 30.0 seconds, at which point the pressure in the flask is found to be 15.0 mm Hg. The experiment is repeated using unknown gas at the same temperature and pressure. After 30.0 seconds, the pressure is found to be 47.4 mm Hg. What is the molar mass of the gas?
a) 4.00 g/mol
b) 16.0 g/mol
c) 28.0 g/mol
d) 32.0 g/mol
e) 83.8 g/mol
a
The lowest frequency available on a radio's AM dial is 570 kHz. What is the wavelength of this light?
a) 1.8 x 10^-7 m
b) 1.8 x 10^-6 m
c) 1.9 x 10^-3 m
d) 5.3 x 10^2 m
e) 5.3 x 10^4 m
d
A microwave oven emits radiation at a frequency of 6.00 x 10^10 Hz. What is the wavelength of this light?
a) 3.98 x 10^-23 m
b) 1.67 x 10^-11 m
c) 5.00 x 10^-3 m
d) 2.00 x 10^-2 m
e) 2.00 x 10^-1 m
c
Place the following regions of the electromagnetic spectrum in order from longest to shortest wavelength.
a) radio> microwave> visible> ultraviolet> gamma ray
b) gamma ray> microwave> radio> visible> ultraviolet
c) ultraviolet> visible> microwave> radio> gamma ray
d) microwave> radio> ultraviolet> visible> gamma ray
e) visible> gamma ray> radio> ultraviolet> microwave
a
Place the following regions of the electromagnetic spectrum in order from highest to lowest energy.
a) infrared> gamma rays> x-rays> visible> radio
b) gamma rays> x-rays> visible> infrared> radio
c) x-rays> gamma rays> infrared> visible> radio
d) radio> x-rays> gamma rays> visible> infrared
e) visible> infrared> radio> x-rays> gamma rays
b
When Cs-137 decays, it emits gamma radiation. The energy of one photon is 1.06 x 10^-13 J. What is the wavelength of this radiation?
a) 1.87 x 10^-12 m
b) 2.08 x 10^-12 m
c) 2.44 x 10^-12 m
d) 1.88 x 10^-11 m
e) 1.58 x 10^-10 m
a
The Schrodinger wave equation
a) proves electrons have positive and negative spins
b) calculates the precise and momentum of an electron at any given time
c) is used to compute the wavelength of small particles
d) can be solved to find the probability of finding an electron in a region of space
e) proves that photons are particles
d
Which of the following sets of quantum numbers refers to a 2s orbital?
a) n=1,l=2,m(little l)=2,m(little s)=+1/2
b) n=1,l=2,m(little l)=1,m(little s)=+1/2
c) n=2,l=2,m(little l)=0,m(little s)=+1/2
d)n=2,l=1,m(little l)=-1,m(little s)=+1/2
e) n=2,l=0,m(little l)=0,m(little s)=+1/2
e
How many orbitals have the following quantum numbers: n=6, l=2, m(little l)=-2
a) 0
b) 1
c) 3
d) 5
e) 6
b
What is the symbol of the atom or ion with the following orbital diagram?
1s: (^v) 2s: (^v) 2p: (^v)(^ )(^ )
a) 5B
b) 7N
c) 8O
d) 16S
e) 9F
c
What is the symbol of the atom or ion with the following orbital diagram?
1s: (^v) 2s: (^v) 2p: (^v)(^v)(^v) 3s: (^v)
3p: (^v)(^v)(^v) 3d: (^v)(^v)(^v)(^ )(^ )
4s: ( )
a) 26Fe
b) 26Fe^2+
c) 27Co^+
d) 28Ni
e) 28Ni^2+
e
What is the correct orbital diagram for phosphorous?
a) 1s: (^v) 2s: (^v) 2p: (^ )(^ )(^ )
b) 1s: (^v) 2s: (^v) 2p: (^v)(^ )( )
c) 1s: (^v) 2s: (^v) 2p: (^v)(^v)(^v) 3s: (^v) 3p: (^v)(^ )( )
d) 1s: (^v) 2s: (^v) 2p: (^v)(^v)(^v) 3s: (^v) 3p: (^ )(^ )(^ )
e) 1s: (^v) 2s: (^v) 2p: (^v)(^v)(^v) 3s: (^ ) 3p: (^v)(^ )(^ )
d
What is the correct orbital diagram for Fe^2+?
a) [Ar] 3d: (^ )(^ )(^ )(^ )( ) 4s: (^v)
b) [Ar] 3d: (^ )(^ )(^ )(^ )(^ ) 4s: (^ )
c) [Ar] 3d: (^ )(^ )(^ )(^ )(^ ) 4s: ( )
d) [Ar] 3d: (^v)(^ )(^ )(^ )(^ ) 4s: ( )
e) [Ar] 3d: (^v)(^v)(^ )( )( ) 4s: ( )
c
In general, ionization energies
a) increase down a group and increase across a period
b) increase down a group and decrease across a period
c) decrease down a group and increase across a period
d) decrease down a group and decrease across a period
e) increase with atomic mass and increase with atomic radii
c
In general, atomic radii
a) increase down a group and decrease across a period
b) increase down a group and increase across a period
c) decrease down a group and decrease across a period
d) are proportional to atomic mass
e) decrease down a group and increase across a period
a
Place the following atoms in order of increasing size: Al, Cl, Mg, O, and P
a) Cl<O<P<Al<Mg
b) Cl<P<Al<Mg<O
c) O<Cl<P<Al<Mg
d) O<Mg<Al<P<Cl
e) none of the above
c
Electronegativity increases
a) moving down a group in the periodic table
b) moving from left to right across the periodic table
c) with increasing atomic mass
d) when electrons are paired
e) with increasing atomic radii
b
What is the expected number of valence electrons for an element in group 15?
a) 0
b) 1
c) 3
d) 5
e) 8
d
Which of the following is a correct Lewis structure for C2H60O?
a) central atoms: O (connected to a H and surrounded by 2 electrons on both the top and bottom), C1 (connected to 2 H's), and C2 (connected to 3 H's)
b) central atoms: O (connected to a H, surrounded by 2 electrons on the top, and double bonded to C1), C1 (connected to 2 H's), and C2 (connected to 3 H's)
c) central atoms: O (in the center, surrounded by 2 electrons on both the top and bottom), C1 (connected to 3 H's), and C2 (connected to 3 H's)
d) answers a and c are correct
e) answers a, b, and c are correct
d
Which Lewis structure is possible for N2O?
a) N1(has 2 electrons on left, triple bond on right), N2(triple bonded to N1 on left, double bonded to O on right), O(double bonded to N2 on left, 2 pairs of valence electrons on right)
b) N1(has 2 electrons on left, triple bond on right), N2(triple bonded to N1 on left,bonded to O on right), O(bonded to N2 on left, 3 pairs of valence electrons on right)
c) N1(has 2 electrons on left, triple bond on right), N2(triple bonded to N1 on left, 2 electrons on top, bonded to O on right), O(bonded to N2 on left, 3 pairs of valence electrons on right)
d) N1(has 2 pairs of electrons on left, double bond on right), N2(double bonded to N1 on left, bonded to O on right), O(bonded to N2 on left, 3 pairs of valence electrons on right)
e) N1(has 2 electrons on left, double bond on right), N2(double bonded to N1 on left, 2 electrons on top, bonded to O on right), O(bonded to N2 on left, 3 pairs of valence electrons on right)
b
Which of the following is not a correct Lewis structure?
NO2: O(2 pairs)-N(1 e)-O(3 pairs)
NO2^-: [O(2 pairs)=N(1 pair)-O(3 pairs)]-
NO: N(2 pairs)=O(2 pairs)
N2O: N(1 pair)triple bondN-O(3 pairs)
a) NO2
b) NO2^-
c) NO
d) N2O
e) all of the above are correct structures
c
Which of the following elements is most likely to form a molecule or ion that exceeds the octet rule?
a) Na
b) S
c) B
d) F
e) C
b
What is the correct Lewis structure of SF4?
a) S in middle connected to 4 F's with 3 pairs each
b) S in middle with 1 pair connected to 4 F's with 3 pairs each
c) S in middle with 3 single bonded F's with 3 pairs each and 1 double bonded F with 3 pairs
d) S in middle with 2 pairs connected to 4 F's with 3 pairs each (making an X)
e) S in middle with 2 pairs on left connected to 4 F's with 3 pairs each (making a K)
b
Which of the following are correct resonance structures of SO3?
1: S in the middle double bonded to 2 O's with 3 pairs on one and 2 pairs on the other and single bonded to another O with 3 pairs
2: S in the middle single bonded to 2 O's with 3 pairs each and double bonded to another O with 2 pairs
3: O in the middle single bonded to 2 O's with 3 pairs each and double bonded to one S with 2 pairs
4: S in the middle double bonded to an O with 2 pairs and single bonded to 2 O's with 3 pairs each
5: S in the middle single bonded to 3 O's, 2 with 3 pairs and 1 with 2 pairs
a) 1 and 5
b) 2 and 4
c) 1, 2, and 4
d) 2, 3, and 4
e) 1, 2, 4, and 5
b
Which of the following species has a Lewis structure with a molecular geometry similar to CS2?
a) H2S
b) NO2^-
c) NO2
d) H2O
e) SCN^-
e
Which of the following species has a Lewis structure with a molecular geometry similar to NH3?
a) CO3^2-
b) BH3
c) H3O^+
d) ICl3
e) SO3
c
Which of the following species has a Lewis structure with a molecular geometry similar to SO3?
a) NH3
b) ICl3
c) CO3^2-
d) SO3^2-
e) PCl3
c
Use VSEPR theory to predict the molecular geometry of SO3^2-.
a) bent
b) tetrahedral
c) square planar
d) triangular planar
e) triangular pyramidal
e
Use VSEPR theory to predict the molecular geometry of SF6.
a) bent
b) linear
c) triangular planar
d) t-shaped
e) octahedral
e
Use VSEPR theory to predict the molecular geometry of NH4^+.
a) triangular pyramidal
b) square pyramidal
c) see-saw
d) tetrahedral
e) triangular planar
d
Which of the following species have the same molecular geometry: XeF4, ClF4^+, SF4, PO4^3-?
a) XeF4 and SF4
b) ClF4^+ and SF4
c) ClF4^+ and PO4^3-
d) XeF4 and ClF4^+
e) XeF4, SF4, and PO4^3-
b
What are the bond angles in a phosphate ion?
a) 90 degrees
b) 109.5 degrees
c) 120 degrees
d) 90 and 120 degrees
e) 180 degrees
b
What are the approximate bond angles in SF4?
a) 90 degrees
b) 109.5 degrees
c) 120 degrees
d) 90 and 120 degrees
e) 180 degrees
d
Which of the following molecules are polar: H2S, CO2, NH3, BH3, and CCl4?
a) BH3
b) H2S and NH3
c) H2S, CO2, and CCl4
d) CO2, NH3, and CCl4
e) NH3, BH3, and CCl4
b
How many sigma and pi bonds are present in the following molecule?
H3C-CH=CH-CH3
a) 8 sigma bonds and 1 pi bond
b) 8 sigma bonds and 2 pi bond
c) 10 sigma bonds and 2 pi bond
d) 11 sigma bonds and 2 pi bond
e) 11 sigma bonds and 1 pi bond
e
Which of the following are state properties?
a) heat flow
b) volume
c) enthalpy
d) answers b and c
e) answers a, b, and c
d
Aluminum has a specific heat of 0.902 J/g x degrees Celsius. How many joules of heat are required to change the temperature of 8.50 grams of aluminum from 25.0 degrees Celsius to 93.4 degrees Celsius?
a) 7.67 J
b) 71.7 J
c) 192 J
d) 483 J
e) 524 J
e
Copper has a specific heat of 0.382 J/g x degrees Celsius. The temperature of an unknown mass of copper increases by 4.50 degrees Celsius when it absorbs 3.97 J of hear. What is the mass of the copper?
a) 2.31 g
b) 4.90 g
c) 6.82 g
d) 8.85 g
e) 46.8 g
a
The heat capacity of 5.00 grams of iron is 2.23 J/degrees Celsius. How mush heat is required to heat the iron by 50.0 degrees Celsius?
a) 0.223 J
b) 22.3 J
c) 112 J
d) 558 J
e) 612 J
c
If 35.0 J is required to heat 50.3 g Hg by 5.00 degrees Celsius, what is the specific heat of mercury?
a) 0.139 J/g x degrees Celsius
b) 0.250 J/g x degrees Celsius
c) 0.572 J/g x degrees Celsius
d) 0.878 J/g x degrees Celsius
e) 1.49 J/g x degrees Celsius
a
Commercial cold packs consist of solid ammonium nitrate and water. NH4NO3 absorbs 330 J of heat per gram dissolved in water. In a coffee-cup calorimeter, 4.00 g of NH4NO3 is dissolved in 75.0 g H2O. Assuming that all the heat is lost from the water (c=4.18 J/g x degrees Celsius, what is the temperature change of the water?
a) 4.2 degrees Celsius
b) 8.4 degrees Celsius
c) 11 degrees Celsius
d) 13 degrees Celsius
e) 19 degrees Celsius
a
All of the following statements are true EXCEPT
a) the enthalpy change of an endothermic reaction is positive
b) at constant pressure the heat flow for a reaction equals the change in enthalpy
c) triangle H for a reaction is equal in magnitude but opposite in sign to triangle H for the reverse reaction
d) enthalpy is a state function
e) enthalpy change is dependent upon the number of steps in a reaction
e
Hydrazine, N2H4, is a liquid used as a rocket fuel. It reacts with oxygen to yield nitrogen gas and water.
N2H4(l) + O2(g) -> N2(g) + 2H2O(l)
The reaction of 3.60 g of N2H4 evolves 69.8 kJ of heat. Calculate the enthalpy change per mole of hydrazine for the above reaction.
a) 7.84 kJ
b) 19.4 kJ
c) 621 kJ
d) 754 kJ
e) 8050 kJ
c
Determine the heat of reaction for the decomposition of one mole of benzene to acetylene
C6H6(l) -> 3C2H2(g)
given the following thermochemical equations:
triangle H= -6271kJ for 2C6H6(l) + 15O2(g) -> 12CO2(g) + 6H2O(g)
triangle H= -2511kJ for 2C2H2(g) + 5O2(g) -> 4CO2(g) + 2H2O(g)
a) 631 kJ
b) 1262 kJ
c) 3760 kJ
d) 6902 kJ
e) 8782 kJ
a
Determine the heat of formation of sulfuric acid, H2SO4(l), from the following thermochemical equations:
triangle H= -2374.6 kJ for S8(s) + 8O2(g) -> 8SO2(g)
triangle H= -3165.8 kJ for S8(s) + 12O2(g) -> 8SO3(g)
triangle H= -132.4 kJ for H2O(l) + SO3(g) -> H2SO4(l)
triangle H= -571.7 kJ for 2H2(g) + O2(g) -> 2H2O(l)
a) -814.0 kJ
b) -1099.9 kJ
c) -2164.7 kJ
d) -3869.9 kJ
e) -6244.5 kJ
a
All of the following statements are true EXCEPT
a) Hess' law states that triangle H for an overall reaction is the sum of the triangle H's for the individual equations
b) the molar enthalpy of formation of a compound is equal to the enthalpy change when one mole of the compound is formed from elements
c) a reaction with a negative enthalpy is exothermic
d) the enthalpy of formation of an element in its most stable state is equal to zero
e) the sum of the enthalpies of formation of the products in a chemical reaction is defined as the enthalpy of reaction
e
Using molar enthalpies of formation, determine the heat of combustion of 1.000 mole of glucose, C6H12O6(s).
standard triangle H (kJ)= -1273.3 for C6H12O6(s)
standard triangle H (kJ)= -393.5 for CO2(g)
standard triangle H (kJ)= -285.8 for H2O(l)
a) -5349.1 kJ
b) -2802.5 kJ
c) -1952.6 kJ
d) -594.0 kJ
e) 594.0 kJ
b
The molar enthalpies of formation for H2O(l) and H2O(g) are -285.8 kJ and -241.8 kJ, respectively. How much heat is released when 25 g of water condenses from the gas to the liquid phase?
a) -2.4 kJ
b) -32 kJ
c) -61 kJ
d) -88 kJ
e) -1100 kJ
c
If not handled carefully, ammonium perchlorate can decompose violently according to the thermochemical equation below
2NH4ClO4(s) -> N2(g) + Cl2(g) + 2O2(g) + 4H2O(g)
triangle H= -375.6 kJ
The enthalpy of formation of H2O(g) is -241.8 kJ. Calculate the enthalpy of formation of ammonium perchlorate.
a) -295.8 kJ
b) -156.4 kJ
c) 66.9 kJ
d) 133.8 kJ
e) 561.1 kJ
a
The thermite reaction is an exothermic process that yields iron metal as a product.
Fe2O3(s) + 2Al(s) -> 2Fe(s) + Al2O3(s)
standard triangle H (kJ/mol) of Fe2O3(s)= -824.2
Al2O3(s)= -1675.7
Using enthalpies of formation, determine the heat released when 5.00 g of Fe2O3(s) reacts with excess Al.
a) -26.7 kJ
b) -171 kJ
c) -243 kJ
d) -850.8 kJ
e) -2720 kJ
a
In which of the reactions below is triangle H not an enthalpy of formation?
a) 2C(s) + O2(g) -> 2CO(g)
b) C(s) + O2(g) -> CO2(g)
c) Mg(s) + Cl2(g) -> MgCl2(s)
d) Ca(s) + .5O2(g) -> CaO(s)
e) both b and c are not enthalpy of formation reactions
a
In which of the reactions below is triangle H an enthalpy of formation?
a) S8(s) + 8O2(g) -> 8SO2(g)
b) CaO(s) + H2O(l) -> Ca(OH)2(s)
c) H2(g) + Cl2(g) + 4O2(g) -> 2HClO4(l)
d) Cu(s) + .5I2(s) -> CuI(s)
e) CH4(g) + 2O2(g) -> CO2(g) + 2H2O(g)
d
Using the bond enthalpies tabulated below, calculate the enthalpy of reaction for the combustion of hydrogen. Hint: the bond enthalpies are approximate enthalpies needed to make or break a chemical bond.
2H2(g) + O2(g) -> 2H2O(g)
bond: H-H, 436
O-H, 464
O-O, 138
O=O, 498
a) -846 kJ
b) -486 kJ
c) -348 kJ
d) -243 kJ
e) 888 kJ
b
Using the bond enthalpies tabulated below, calculate the enthalpy of reaction for the combustion of hydrogen. Hint: the bond enthalpies are approximate enthalpies needed to make or break a chemical bond.
2C6H6(g) + 7O2(g) -> 4CO2(g) + 6H2O(g)
bond: H-H, 436
C-H, 414
C-C, 347
C-O, 351
C=O, 715
O-O, 138
O=O, 498
O-H, 464
a) -2834 kJ
b) -2140 kJ
c) -1174 kJ
d) -644 kJ
e) -322 kJ
b
The first law of thermodynamics states that
a) the amount of work done on a system is independent of the pathway
b) the heat flow in or out of a system is independent of the pathway
c) the total energy change of a system is equal to the sum of the heat absorbed and the work done on the system
d) both a and c
e) both b and c
c
Calculate triangle E of a gas for a process in which the gas absorbs 25 J of heat and does 7 J of work by expanding.
a) -32 J
b) -18 J
c) +18 J
d) +32 J
e) +180 J
c
Calculate triangle E of a gas for a process in which the gas evolves 12 J of heat and does 8 J of work by expanding.
a) -20 J
b) -4 J
c) +4 J
d) -20 J
e) -96 J
d
Calculate triangle E of a gas for a process in which the gas evolves 24 J of heat and has 9 J of work done on it.
a) -33 J
b) -15 J
c) +15 J
d) +33 J
e) -220 J
b
All of the following statements are false for a chemical system in a dynamic equilibrium EXCEPT
a) the concentrations of reactants and products must be equal
b) the reaction is endothermic
c) the reaction is exothermic
d) the chemical reaction proceeds in the forward direction until all reactants are consumed
e) the concentrations of reactants and products remain constant over time
e
The partial pressure of a gas is
a) directly proportional to the number of moles of the gas
b) proportional to the gas constant, R
c) directly proportional to the volume of the gas
d) always constant during a chemical reaction
e) inversely proportional to the temperature of the gas
a
A large equilibrium constant
a) results from the addition of a catalyst to a reaction mixture
b) indicates that the reaction favors the formation of products
c) indicates that the reaction favors the formation of reactants
d) indicates that a reaction has a large rate constant
e) indicates that a reaction has a small rate constant
e
What is the correct equilibrium constant expression for the formation of ammonia gas from nitrogen gas and hydrogen gas?
a) K=P of NH3/ P of N2 x P of H2
b) K=(2P of NH3)^2/ P of N2 x (3P of H2)^3
c) K= P of N2 x (3P of H2)/ (2P of NH3)
d) K= (P of NH3)^2/ P of N2 x (P of H2)^3
e) K=P of N2 x (P of H2)^3/ (P of NH3)^2
d
What is the correct equilibrium constant expression for the following reaction?
CO2(g) + 2H2O(g) <-> CH4(g) + 2O2(g)
a) K= P of CO2 x P of H2O/ P of CH4 x P of O2
b) K= P of CH4 x P of O2/ P of CO2 x P of H2O
c) K= P of CH4 x (P of O2)^2/ P of CO2 x (P of H2O)^2
d) K= P of CO2 x (P of H2O)^2/ P of CH4 x (P of O2)^2
e) none of the above
c
What is the correct equilibrium constant expression for the following reaction?
C4H10(g) + 13/2O2(g) <-> 4CO2(g) + 5H2O(g)
a) K=P of CO2 x P of H2O/ P of C4H10 x P of O2
b) K=(P of CO2)^4 x (P of H2O)^5/ P of C4H10 x (P of O2)^13/2
c) K=(P of CO2)^8 x (P of H2O)^10/ (P of C4H10)^2 x (P of O2)^13
d) K=(4P of CO2)^4 x (5P of H2O)^5/ P of C4H10 x (13/2P of O2)^13/2
e) K=P of C4H10 x (P of O2)^13/2/ (P of CO2)^4 x (P of H2O)^5
b
What is the correct equilibrium constant expression for the following reaction?
H2(g) + I2(s) <-> 2HI(g)
a) K= (P of HI)^2/P of H2
b) K= (P of HI)/(P of H2)^.5
c) K= (P of HI)^.5/P of I2 x P of H2
d) K= (P of HI)^2/P of I2 x P of H2
e) K= (P of HI)^2/(P of I2)^2 x (P of H2)^2
a
What is the correct equilibrium constant expression for the following reaction?
CaCO3(s) <-> CaO(s) + CO2(g)
a) K=P of CO2/P of CaCO3
b) K=1/P of CO2
c) K=P of CaO x P of CO2/P of CaCO3
d) K=P of CO2
e) none of the above
d
Write the balance chemical reaction which corresponds to the following equilibrium constant expression.
K=(P of CO2)^2/ (P of CO)^2 x P of O2
a) 2CO2(g) <-> 2CO(g) + O2(g)
b) CO2(g) <-> CO(g) + .5O2(g)
c) 2CO(g) + O2(g) <-> 2CO2(g)
d) CO(g) + .5O2(g) <-> CO2(g)
e) none of the above
c
Write the balanced chemical reaction which corresponds to the following equilibrium constant expression.
K= (P of N2O5)^2/P of O2 x (P of NO2)^4
a) 4N2O5(g) <-> O2(g) + 2NO2(g)
b) 2N2O5(g) <-> O2(g) + 4NO2(g)
c) N2O5(g) <-> O2(g) + NO2(g)
d) O2(g) + 2NO2(g) <-> 4N2O5(g)
e) O2(g) + 4NO2(g) <-> 2N2O5(g)
e
Use the equilibrium constants for the following reactions
2NO(g) <-> N2(g) + O2(g)
K1=2.4 x 10^30
2NO(g) + O2(g) <-> 2NO2(g)
K2= 2.4 x 10^12
to determine the equilibrium constant for the reaction below.
N2(g) + 2O2(g) <-> 2NO2(g)
a) 1.7 x 10 ^-43
b) 1.0 x 10^-18
c) 5.8 x 10^18
d) 2.4 x 10^30
e) 5.8 x 10^42
b
Use the equilibrium constants for the following reactions at 700 degrees Celsius.
2SO2(g) + O2(g) <-> 2SO3(g)
K1= 4.8
2NO(g) + O2(g) <-> 2NO2(g)
K2= 16
to determine the equilibrium constant for the following reaction.
SO3(g) + NO(g) <-> SO2(g) + NO2(g)
a) 0.30
b) 0.55
c) 0.85
d) 1.8
e) 3.3
d
Given the following equilibrium equations,
2N2O(g) <-> 2N2(g) + O2(g)
K1= 8.3 x 10^34
N2O4(g) <-> 2NO2(g)
K2= 4.6 x 10^-3
2NO2(g) <-> N2(g) + 2O2(g)
K3= 5.9 x 10^16
calculate K for the decomposition of dinitrogen tetraoxide to nitrogen dioxide and oxygen.
2N2O4(g) <-> 2N2O(g) + 3O2(g)
K4= ?
a) 1.1 x 10^-41
b) 1.3 x 10^-20
c) 8.9 x 10^-7
d) 3.3 x 10^21
e) 2.3 x 10^49
c
For which of the following reactions does Kc equal Kp?
a) Sn(s) + 2H2O(g) <-> SnO2(s) + 2H2(g)
b) 2C2H6(g) + 7O2(g) <-> 4CO2(g) + 6H2O(g)
c) NH4Cl(s) <-> NH3(g) + HCl(g)
d) N2(g) + 3H2(g) <-> 2NH3(g)
e) CaCO3(s) <-> CaO(s) + CO2(g)
a
For which of the following reactions does Kc equal Kp?
a) C2H4(g) + H2(g) <-> C2H6(g)
b) 2NO(g) + O2(g) <-> 2NO2(g)
c) 2S(s) + 3O2(g) <-> 2SO3(g)
d) CaCOS(s) <-> CaO(s) + CO2(g)
e) SO2(g) + NO2(g) <-> SO3(g) + NO(g)
e
Which of the following reactions is a heterogeneous equilibria expression?
a) 2NO(g) + O2(g) <-> 2NO2(g)
b) 2NH3(g) <-> N2(g) + 3H2(g)
c) 2H2(g) + O2(g) <-> 2H2O(g)
d) 2S(s) + 3O2(g) <-> 2SO3(g)
e) C2H4(g) + H2(g) <-> C2H6(g)
d
For the reaction below, the partial pressures of gases at equilibrium are as follows: H2=7.1 x 10^-5 atm, Cl2=2.5 x 10^-6 atm, and HCl=3.0 atm. What is the value of the equilibrium constant, Kp?
H2(g) + Cl2(g) <-> 2HCl(g)
a) 2.0 x 10^-11
b) 5.9 x 10^-11
c) 1.6 x 10^-9
d) 1.7 x 10^10
e) 5.1 x 10^10
e
At 25 degrees Celsius, the decomposition of dinitrogen tetraoxide
N2O4(g) <-> 2NO2(g)
has an equilibrium constant (Kp) of 0.144. At equilibrium, the total pressure of the system is 0.500 atm. What is the partial pressure of each gas?
a) N2O4=0.206 atm; NO2=0.294 atm
b) N2O4=0.212 atm; NO2=0.288 atm
c) N2O4=0.288 atm; NO2=0.212 atm
d) N2O4=0.294 atm; NO2=0.206 atm
e) N2O4=0.437 atm; NO2=0.063 atm
d
At sufficiently high temperatures, ammonium iodide decomposes to ammonia and hydrogen iodide.
NH4I(s) <-> NH3(g) + HI(g)
A mass of 30.0 g of NH4I is sealed in a 5.00-L flask and heated to 673 K. If 23.9 g NH4I(s) remain unreacted when the system has reached equilibrium, what is the equilibrium constant (Kp) for the reaction? (R=0.0821 L x atm/mol x K)
a) 0.15
b) 0.22
c) 0.47
d) 0.59
e) 0.89
b
Hydrogen iodide can decompose into hydrogen and iodine gases.
2HI(g) <-> H2(g) + I2(g)
Kp for the reaction is 0.016. If 0.200 atm of HI(g) is sealed in a flask, what is the pressure of each gas when equilibrium is established?
a) HI=0.110 atm; H2=0.014 atm; I2=0.014 atm
b) HI=0.151 atm; H2=0.025 atm; I2=0.025 atm
c) HI=0.151 atm; H2=0.049 atm; I2=0.049 atm
d) HI=0.156 atm; H2=0.022 atm; I2=0.022 atm
e) HI=0.160 atm; H2=0.020 atm; I2=0.020 atm
e
Hydrogen iodide can decompose into hydrogen and iodine gases.
2HI(g) <-> H2(g) + I2(g)
Kp for the reaction is 0.016. If 0.350 atm of HI(g) is sealed in a flask, what is the total pressure of the system when equilibrium is established?
a) 0.258 atm
b) 0.279 atm
c) 0.350 atm
d) 0.385 atm
e) 0.412 atm
c
Assuming the reaction below is at equilibrium, which of the following changes will drive the reaction to the right?
C(s) + O2(g) <-> CO2(g)
triangle H= -393.5 kJ/mol
1. increasing the temperature
2. removing CO2(g)
3. adding C(s)
a) 1 only
b) 2 only
c) 3 only
d) 1 and 2
e) 2 and 3
b
If the value of Q is less than Kp, then
a) the system is in equilibrium
b) a catalyst is necessary to achieve equilibrium
c) the reaction will go left or right depending upon the reaction stoichiometry
d) the reaction will proceed to the right until equilibrium is established
e) the reaction will proceed to the left until equilibrium is established
d
Which of the following changes will increase the amount of oxygen produced in the following equilibrium system?
2HgO(s) <-> 2Hg(l) + O2(g)
triangle H= +181.6 kJ
a) increasing the amount of HgO(s)
b) removing Hg(l)
c) increasing the temperature of the system
d) decreasing the volume of the reaction vessel
e) increasing the pressure on the system
c
Hydrogen and oxygen react to form water.
2H2(g) + O2(g) <-> 2H2O(g)
triangle H=-483.6 kJ
The equilibrium constant for this reaction is 5.3 x 10^84 at 298 K. What is the equilibrium constant at 1500 K?
(R=8.31 J/mol x K)
a) 5.8 x 10 ^16
b) 9.1 x 10^31
c) 4.3 x 10^42
d) 1.1 x 10^84
e) 9.4 x 10^84
a
The reaction of nitrogen with hydrogen to form ammonia is thermodynamically favorable.
N2(g) + 3H2(g) <-> 2NH3(g)
triangle H= -92.2 kJ
The equilibrium constant for this reaction is 6.0 x 10^5 at 298 K. At what temperature is the equilibrium constant equal to 1.0 x 10^3? (R=8.31 J/mol x K)
a) 85 K
b) 110 K
c) 310 K
d) 360 K
e) 2800 K
d