Introduction to General, Organic & Biological Chemistry, 12e (Timberlake)
Chapter 7 Chemical Quantities and Reactions
7.1 Multiple-Choice Questions
1) One mole of particles of any substance contains how many particles?
A) particles
B) 3 × particles
C) 3 × particles
D) 6.02 × particles
E) 6.02 × particles
2) Avogadro’s number is the number of ________.
A) particles in 1 mole of a substance
B) amu in 1 mole of a substance
C) grams in 1 mole of a substance
D) moles in 6.02 × g of an element
E) moles in 6.02 × amu of an element
3) One mole of copper(II) sulfate, CuS , contains ________ O atoms.
A) 4
B) 6.02 ×
C) 1.51 ×
D) 2.41 ×
E) 2.41 ×
4) 0.400 mole of sucrose, , contains ________ C atoms.
A) 12
B) 6.02 ×
C) 5.02 ×
D) 2.89 ×
E) 4.80
5) One mole of copper(II) sulfate, CuS , contains ________ moles of O.
A) 4
B) 6.02 ×
C) 1.51 ×
D) 2.41 ×
E) 2.41 ×
6) 0.400 mole of sucrose, , contains ________ moles of C.
A) 12
B) 6.02 ×
C) 5.02 ×
D) 2.89 ×
E) 4.80
7) How many moles of carbon atoms are there in 0.500 mole of ?
A) 0.500 mole
B) 1.00 mole
C) 3.00 moles
D) 6.02 × moles
E) 4.00 moles
8) The molar mass of potassium is ________.
A) 19.00 g/mole
B) 31.00 g/mole
C) 6.02 × g/mole
D) 39.10 g/mole
E) 15.02 g/mole
9) One mole of helium gas weighs ________.
A) 1.000 g
B) 2.002 g
C) 3.003 g
D) 4.003 g
E) 8.006 g
10) Calculate the molar mass of potassium chloride, KCl.
A) 74.55 g/mole
B) 54.55 g/mole
C) 6.745 g/mole
D) 67.45 g/mole
E) 19.00 g/mole
11) What is the molar mass of copper(II) sulfate, CuS ?
A) 16.00 g/mole
B) 63.60 g/mole
C) 111.6 g/mole
D) 159.6 g/mole
E) 319.2 g/mole
12) Calculate the molar mass of magnesium chloride, Mg .
A) 24.31 g/mole
B) 95.21 g/mole
C) 125.9 g/mole
D) 59.76 g/mole
E) 70.90 g/mole
13) What is the molar mass of sodium phosphate, ?
A) 69.96 g/mole
B) 118.0 g/mole
C) 163.9 g/mole
D) 226.1 g/mole
E) 354.0 g/mole
14) What is the molar mass of sucrose ( )?
A) 29.02 g/mole
B) 50.23 g/mole
C) 210.0 g/mole
D) 342.3 g/mole
E) 182.0 g/mole
15) One mole of neon atoms has a mass of ________.
A) 6.02 × g
B) 14.01 g
C) 10.01 g
D) 20.18 g
E) 22.99 g
16) The molar mass of is ________.
A) 76.09 g/mole
B) 60.09 g/mole
C) 29.02 g/mole
D) 69.02 g/mole
E) 52.01 g/mole
17) The molar mass of calcium hydroxide, , is ________.
A) 58.09 g/mole
B) 57.09 g/mole
C) 74.10 g/mole
D) 114.2 g/mole
E) 54.02 g/mole
18) What is the molar mass of , a substance formerly used in medicine as an antacid?
A) 71.28 g/mole
B) 118.3 g/mole
C) 150.3 g/mole
D) 214.3 g/mole
E) 262.9 g/mole
19) How many moles of water, O, are present in 75.0 g O?
A) 4.41 moles
B) 4.16 moles
C) 75.0 moles
D) 7.50 moles
E) 1.35 × moles
20) 0.100 mole of lithium has a mass of ________.
A) 3.00 g
B) 0.300 g
C) 6.94 g
D) 0.694 g
E) 0.700 g
21) 4.00 moles of sodium have a mass of ________.
A) 4.60 g
B) 11.0 g
C) 23.0 g
D) 44.0 g
E) 92.0 g
22) How many moles of are in 15.0 g of ?
A) 0.172 moles
B) 2.61 × 103 moles
C) 0.111 moles
D) 0.0861 moles
E) 0.119 moles
23) 3.00 moles of have a mass of ________.
A) 138 g
B) 46.0 g
C) 30.0 g
D) 90.0 g
E) 45.0 g
24) How many grams of are there in 0.500 mole of ?
A) 79.9 g
B) 35.9 g
C) 63.8 g
D) 51.9 g
E) 160. g
25) How many grams of glucose ( ) are in 3.55 moles of glucose?
A) 180. g
B) 640. g
C) 103 g
D) 426 g
E) 50.7 g
26) A chemical equation is balanced when ________.
A) the total number of molecules is the same in reactants and products
B) the total number of ions is the same in reactants and products
C) the sum of the coefficients of the reactants is equal to the sum of the coefficients of the
products
D) the number of atoms of each element is the same in reactants and products
E) the charge on each atom is the same in reactants and products
27) In any balanced chemical equation, the number of each type of atom on both sides of the
equation is ________.
A) doubled
B) the same
C) decreased by one
D) increased by one
E) dependent on the temperature
28) Which of the following gives the balanced equation for this reaction?
+ Ca → +
A) + +
B) + Ca → + 3
C) 2 + Ca → + 6
D) 2 + 3Ca → + 6
E) + Ca → +
29) Which of the following correctly gives the correct coefficients for the reaction below?
+ → + O
A) 1, 1, 1, 1
B) 1, 2, 1, 4
C) 2, 4, 2, 8
D) 1, 4, 1, 4
E) 2, 4, 2, 4
30) What coefficient is placed in front of to complete the balancing of the following
equation?
+ ? → 5 + 4 O
A) 1
B) 3
C) 5
D) 7
E) 9
31) What is the coefficient of hydrogen, , when the following equation is balanced?
Al + → + ?
A) 1
B) 2
C) 3
D) 4
E) 5
Pentane ( ) reacts with oxygen ( ) to form carbon dioxide ( ) and water ( O)
according to the following reaction. Answer the following question(s) about this reaction.
+ ? → ? + ? O
32) What is the coefficient for oxygen in the balanced equation?
A) 2
B) 4
C) 5
D) 6
E) 8
33) What is the coefficient for carbon dioxide in the balanced equation?
A) 2
B) 4
C) 5
D) 6
E) 8
34) What is the coefficient for water in the balanced equation?
A) 2
B) 4
C) 5
D) 6
E) 8
35) In this reaction, what is the coefficient for calcium oxide?
CaO + CO2 → CaCO3
A) 1
B) 2
C) 3
D) 4
E) 5
36) In this reaction, what is the correct coefficient for sodium chloride?
Pb(N + ? NaCl → PbC + ? NaN
A) 1
B) 2
C) 3
D) 4
E) 5
37) In the following reaction, what is the correct coefficient for aluminum chloride?
Al + → Al
A) 1
B) 2
C) 3
D) 4
E) 5
38) For the following reaction, what is the correct coefficient for the ?
Fe + HCl → FeC +
A) 1
B) 2
C) 3
D) 4
E) 5
39) What is the classification for this unbalanced reaction?
Fe + HCl → FeC +
A) combustion
B) combination
C) decomposition
D) single replacement
E) double replacement
40) In a ________ reaction, two or more elements or compounds form one product.
A) decomposition
B) single replacement
C) combustion
D) double replacement
E) combination
41) The following reaction is an example of a ________ reaction.
+ 7 → 5 + 4 O
A) combination
B) single replacement
C) combustion
D) decomposition
E) double replacement
42) The following reaction takes place when an electric current is passed through water. It is an
example of a ________ reaction.
O 2 +
A) combination
B) single replacement
C) combustion
D) decomposition
E) double replacement
43) What is the classification for this reaction?
S + O → S
A) decomposition
B) combination
C) replacement
D) double replacement
E) combustion
44) The reaction of carbon with oxygen to produce carbon monoxide is an example of which
class of reaction?
2C + → 2CO
A) single replacement
B) double replacement
C) combination
D) catalytic
E) endothermic
45) Which of the following is an oxidation-reduction reaction?
A) Ca + → Ca + 2NaCl
B) KOH + → O +
C) + → 2NO
D) + NaCl → AgCl +
E) + 6KOH → 2 + 3
46) What is oxidized and what is reduced in the following reaction?
2Al + 3 → 2
A) Al is oxidized and is reduced.
B) AlBr3 is reduced and is oxidized.
C) Al is reduced and is oxidized.
D) is reduced and Al is oxidized.
E) is oxidized and Al is reduced.
47) In an oxidation-reduction reaction, the substance oxidized always ________.
A) takes on oxygen atoms
B) loses electrons
C) gives up hydrogen atoms
D) gains electrons
E) becomes a charged species
48) In this reaction, what is the substance oxidized?
Zn + 2 HCl → ZnCl2 + H2
A) chlorine
B) zinc chloride
C) hydrogen
D) zinc
E) oxygen
49) In an oxidation-reduction reaction, the substance reduced always ________.
A) takes on oxygen atoms
B) loses electrons
C) gives up hydrogen atoms
D) gains electrons
E) becomes a charged species
50) Given the following equation, what is the correct form of the conversion factor needed to
convert the number of moles of to the number of moles of produced?
4Fe + 3 → 2
A)
B)
C)
D)
E)
For the following question(s), consider the following equation.
2Mg + → 2MgO
51) The number of moles of oxygen gas needed to react with 4.0 moles of Mg is ________.
A) 1.0 mole
B) 2.0 moles
C) 3.0 moles
D) 4.0 moles
E) 6.0 moles
52) The number of moles of MgO produced when 0.20 mole of reacts completely is
________.
A) 0.10 mole
B) 0.20 mole
C) 0.40 mole
D) 0.60 mole
E) 0.80 mole
53) What is the correct form of the conversion factor needed to convert the number of moles of
O to the number of moles of produced?
A)
B)
C)
D)
E)
54) When 2 moles of are allowed to react, how many moles of O also react?
A) 1 mole
B) 4 moles
C) 6 moles
D) 8 moles
E) 12 moles
55) When 4 moles of aluminum are allowed to react with an excess of chlorine gas, , how
many moles of aluminum chloride are produced?
2Al + 3 → 2Al
A) 1 mole
B) 2 moles
C) 3 moles
D) 4 moles
E) 5 moles
56) In the reaction of nitrogen gas, , with hydrogen gas, , to form ammonia gas, NH3, how
many moles of hydrogen are needed to react with two moles of nitrogen?
+ 3 → 2
A) 2 moles
B) 4 moles
C) 6 moles
D) 8 moles
E) 5.710 moles
For the following question(s), consider the following equation.
2Mg + → 2MgO
57) How many grams of magnesium are needed to react with 16 g of ?
A) 0.50 g
B) 1.0 g
C) 12 g
D) 24 g
E) 48 g
58) How many grams of MgO are produced when 40.0 grams of react completely with Mg?
A) 40.3 g
B) 50.4 g
C) 60.5 g
D) 101 g
E) 202 g
59) How many grams of hydrogen are needed to produce 1.80 g of water according to this
equation?
2 + → 2 O
A) 0.101 g
B) 0.180 g
C) 0.201 g
D) 2.01 g
E) 4.02 g
60) In the reaction of silver nitrate with sodium chloride, how many grams of silver chloride will
be produced from 100. g of silver nitrate when it is mixed with an excess of sodium chloride?
The equation for the reaction is below.
AgN + NaCl → AgCl + NaN
A) 107.9 g
B) 169.9 g
C) 84.4 g
D) 0.589 g
E) 58.9 g
For the following question(s), consider the following balanced equation.
+ 6 O → 3 + 2
61) When 36.0 g of O react, how many grams of are produced?
A) 34.0 g
B) 10.0 g
C) 5.67 g
D) 11.3 g
E) 102 g
62) How many grams of O are needed to produce 150 g of ?
A) 46 g
B) 18 g
C) 130 g
D) 93 g
E) 23 g
63) Find the mass of that is produced when 25.0 grams of reacts with HCl according
to the following equation.
+ 6HCl → 2 + 3 O
A) 155 g
B) 72.9 g
C) 65.3 g
D) 32.6 g
E) 16.3 g
64) How many grams of NO are required to produce 145 g of in the following reaction?
4 + 6NO → 5 + 6 O
A) 186 g
B) 155 g
C) 125 g
D) 129 g
E) 145 g
65) How many grams of are produced when 125 g of reacts as shown in the following
balanced equation?
4 + 6NO → 5 + 6 O
A) 206 g
B) 257 g
C) 165 g
D) 7.35 g
E) 145 g
66) How many grams of are produced from 125 g of and excess ?
+ 2 → + 2 O
A) 125 g
B) 62.5 g
C) 172 g
D) 85.9 g
E) 250. g
67) The ________ is the minimum energy needed for a chemical reaction to begin.
A) reaction energy
B) activation energy
C) energy of reactants
D) energy of products
E) heat of reaction
68) A reaction that releases energy as it occurs is classified as a(n) ________.
A) endothermic reaction
B) exothermic reaction
C) oxidation-reduction reaction
D) catalyzed reaction
E) decomposition reaction
69) What type of reaction is: + 2 → + 2 O + 218 kcal?
A) an endothermic reaction
B) an exothermic reaction
C) a single replacement reaction
D) a combination reaction
E) a decomposition reaction
70) If the reaction shown below is exothermic, the energy level of the reactants is ________.
+ → O
A) lower than that of the products
B) higher than that of the products
C) the same as that of the products
D) possibly lower, possibly higher than that of the products
E) higher than the activation energy of the reaction
71) Any reaction that absorbs 150 kcal of energy can be classified as ________.
A) endothermic
B) exothermic
C) activated
D) reduction
E) oxidation
72) The ________ is the energy difference between reactants and products in a chemical
reaction.
A) transition energy
B) activation energy
C) product energy
D) overall energy
E) heat of reaction
7.2 Bimodal Questions
1) In this reaction, what is the correct coefficient for hydrogen gas?
? H2 + ? O2 → ? H2O
A) 1
B) 2
C) 3
D) 4
E) 5
Barium chloride and sodium sulfate react according to the following equation.
BaCl2 + Na2SO4 → BaSO4 + 2NaCl
Answer the following question(s) about this reaction.
2) How many moles of barium sulfate are produced from 0.1 mole of barium chloride?
A) 0.01 mole
B) 0.1 mole
C) 0.2 mole
D) 1 mole
E) 2 moles
3) How many grams of sodium chloride can be produced from 50. grams of barium chloride?
A) 2.0 g
B) 14 g
C) 28 g
D) 59 g
E) 208 g
4) How many grams of barium chloride are needed to make 100. grams of barium sulfate?
A) 44.9 g
B) 89.2 g
C) 208 g
D) 233 g
E) 46.6 g
Answer the question(s) below about the following reaction.
2 → 2 O +
5) This is an example of a ________ reaction.
A) combustion
B) combination
C) decomposition
D) single replacement
E) double replacement
6) How many moles of oxygen gas can 5.0 moles of hydrogen peroxide (H2O2) produce, if
decomposition is complete?
A) 5.0 moles
B) 2.5 moles
C) 1.0 mole
D) 2.0 moles
E) 10. moles
7) How many grams of water will 100. grams of hydrogen peroxide produce?
A) 36.0 g
B) 360. g
C) 5.88 g
D) 53.0 g
E) 106 g
8) How many grams of hydrogen peroxide are needed to produce 25.0 g of oxygen?
A) 106 g
B) 26.6 g
C) 5.88 g
D) 25.0 g
E) 53.2 g
9) How many moles of hydrogen peroxide (H2O2) are needed to produce 5.0 moles of water?
A) 1.0 mole
B) 2.0 moles
C) 2.5 moles
D) 4.0 moles
E) 5.0 moles
7.3 Short Answer Questions
1) The number of particles in 1 mole of hydrogen gas is ________.
2) The molar mass of copper(II) nitrate, Cu(N is ________.
3) What is the mass, in grams, of 1.00 mole of argon gas?
4) When the following equation is balanced, the coefficient of O2 is ________.
CH4 + O2 → CO2 + O
5) When the following equation is balanced, the coefficient of O2 is ________.
C2H6 + O2 → CO2 + O
6) What type of reaction is the following?
2KCl → 2KCl + 3
7) What type of reaction is the following?
Zn + 2HCl → Zn +
8) What type of reaction is the following?
2 + 5 → 4C + O
9) Which reactant is oxidized in the following reaction?
Zn + 2HCl → Zn +
10) Acetylene gas, , reacts with oxygen according to the following equation. If 1 mole of
acetylene react completely with sufficient oxygen, how many moles of carbon dioxide are
produced?
2 + 5 → 4C + O
11) When 25.0 g of KCl reacts, how many grams of O2 are produced?
2KCl → 2KCl + 3
12) Is the following reaction exothermic or endothermic?
C2H6 + O2 → CO2 + O +1300 kJ
1) Avogadro’s number is the number of grams in a mole.
2) The molar mass of silver is 47 g/mole.
3) The molar mass of magnesium is 24.31 g/mole.
4) The mass of one mole of water is 18.02 g.
5) The molar mass of chlorine gas is 35.45 g/mole.
6) The molar mass of copper(II) chloride is 134.5 g/mole.
7) The following reaction is correctly balanced.
KCl → KCl +
8) The following reaction is correctly balanced.
2 + 5 → 4C + O
31
9) The following is a decomposition reaction.
2KCl → 2KCl + 3
10) The following is a double replacement reaction.
2 + 5 → 4C + O
11) In the following reaction Al is oxidized.
2Al + 3 → 2
12) In the following reaction C is reduced.
2C + → 2CO
13) In the reaction of hydrogen gas with oxygen gas to produce water, 1 mole of oxygen gas can
produce 2 moles of water, given sufficient hydrogen available.
14) In the following reaction, 20.0 g of Al will react completely with 30.0 g of Br2.
2Al + 3 → 2
15) In the following reaction, when 100. g of Br2 reacts, 111 g of AlBr3 is formed.
2Al + 3 → 2
16) The following reaction is endothermic.
2 + 5 → 4C + O + 310 kcal