Deck 3: Chemical Reactions and Reaction Stoichiometry

Question 1

Which of the following are decomposition reactions?
1. CH₄ (g) + O₂ (g) $\rightarrow$ CO₂ (g) + H₂O (l)
2. CaO (s) + CO₂ (g) $\rightarrow$ CaCO₃ (s)
3. Mg (s) + O₂(g) $\rightarrow$ MgO (s)
4. PbCO₃ (s) $\rightarrow$ PbO (s) + CO₂ (g)

A) 1, 2, and 3
B) 4 only
C) 1, 2, 3, and 4
D) 2 and 3
E) 2, 3, and 4

Answer 1

4 only

Question 2

When a hydrocarbon burns in air,what component of air reacts?

A)oxygen
B)nitrogen
C)carbon dioxide
D)water
E)argon

Answer 2

oxygen

Question 3

The molecular weight of the acetic acid (CH₃CO₂H),rounded to the nearest integer,is ________ amu.

A)60
B)48
C)44
D)32

Answer 3

60

Question 4

When a hydrocarbon burns in air,a component produced is ________.

A)oxygen
B)nitrogen
C)carbon
D)water
E)argon

Question 5

The formula weight of potassium dichromate (K₂Cr₂O₇)is ________ amu.

A)107.09
B)255.08
C)242.18
D)294.18
E)333.08

Question 6

Of the reactions below,which one is not a combination reaction?

A)C + O₂ → CO₂
B)2Mg + O₂ → 2MgO
C)2N₂ + 3H₂ → 2NH₃
D)CaO + H₂O → Ca(OH)₂
E)2CH₄ + 4O₂ → 2CO₂ + 4H₂O

Question 7

Which of the following are combustion reactions?
1. CH4 (g) + O₂ (g) → CO₂ (g) + H₂O (l)
2. CaO (s) + CO₂ (g) → CaCO₃ (s)
3. PbCO₃ (s) → PbO (s) + CO₂ (g)
4. CH₃OH (l) + O₂ (g) → CO₂ (g) + H₂O (l)

A) 1 and 4
B) 1, 2, 3, and 4
C) 1, 3, and 4
D) 2, 3, and 4
E) 3 and 4

Question 8

The formula weight of silver chromate (Ag₂CrO₄)is ________ amu.

A)159.87
B)223.87
C)331.73
D)339.86
E)175.87

Question 9

What is the formula weight of lead iodide (PbI₂)?

A)334.1
B)168.7
C)295.6
D)461.0
E)668.2

Question 10

AA

Question 11

What is the formula weight of magnesium fluoride (MgF₂)?

A)86.6
B)43.3
C)62.3
D)67.6
E)92.9

Question 12

AA

Question 13

The formula of nitrobenzene is C₆H₅NO₂.The molecular weight of this compound is ________ amu.

A)107.11
B)43.03
C)109.10
D)123.11
E)3.06

Question 14

AA

Question 15

When the following equation is balanced,the coefficients are ________. C₈H₁₈ + O₂ → CO₂ + H₂O

A)2, 3, 4, 4
B)1, 4, 8, 9
C)2, 12, 8, 9
D)4, 4, 32, 36
E)2, 25, 16, 18

Question 16

AA

Question 17

The reaction used to inflate automobile airbags ________.

A)produces sodium gas
B)is a combustion reaction
C)is a combination reaction
D)violates the law of conservation of mass
E)is a decomposition reaction

Question 18

The formula weight of ammonium sulfate ((NH₄)₂SO₄),rounded to the nearest integer,is ________ amu.

A)100
B)118
C)116
D)132
E)264

Question 19

AA

Question 20

Which of the following are combination reactions?
1.CH₄ (g) + O₂ (g) → CO2 (g) + H2O (l)
2.CaO (s) + CO₂ (g) → CaCO₃ (s)
3.Mg (s) + O2(g) → MgO (s)
4.PbCO₃ (s) → PbO (s) + CO₂ (g)

A) 1, 2, and 3
B) 2 and 3
C) 1, 2, 3, and 4
D) 4 only
E) 2, 3, and 4

Question 21

AA

Question 22

Of the reactions below,which one is a decomposition reaction?

A)NH₄Cl → NH₃ + HCl
B)2Mg + O₂ → 2MgO
C)2N₂ + 3H₂ → 2NH₃
D)2CH₄ + 4O₂ → 2CO₂ + 4H₂O
E)Cd(NO₃)₂ + Na₂S → CdS + 2NaNO₃

Question 23

AA

Question 24

Which one of the following substances is the product of this combination reaction?
Al (s)+ I₂(s)→ ________

A)AlI₂
B)AlI
C)AlI₃
D)Al₂I₃
E)Al₃I₂

Question 25

AA

Question 26

The formula weight of a substance is ________.

A)identical to the molar mass
B)the same as the percent by mass weight
C)determined by combustion analysis
D)the sum of the atomic weights of each atom in its chemical formula
E)the weight of a sample of the substance

Question 27

The formula weight of calcium nitrate (Ca(NO₃)₂),rounded to one decimal place,is ________ amu.

A)102.1
B)164.0
C)204.2
D)150.1
E)116.1

Question 28

AA

Question 29

Which one of the following is not true concerning automotive air bags?

A)They are inflated as a result of a decomposition reaction.
B)They are loaded with sodium azide initially.
C)The gas used for inflating them is oxygen.
D)The two products of the decomposition reaction are sodium and nitrogen.
E)A gas is produced when the air bag activates.

Question 30

AA

Question 31

A sample of CH₄O with a mass of 32.0 g contains ________ molecules of CH₄O.

A)5.32 × 10^-23
B)1.00
C)1.88 × 10²²
D)6.02 × 10²³
E)32.0

Question 32

AA

Question 33

The mass % of H in methane (CH₄)is ________.

A)25.13
B)4.032
C)74.87
D)92.26
E)7.743

Question 34

AA

Question 35

The mass % of C in methane (CH₄)is ________.

A)25.13
B)133.6
C)74.87
D)92.26
E)7.743

Question 36

Calculate the percentage by mass of oxygen in Pb(NO₃)₂.

A)9.7
B)14.5
C)19.3
D)29.0
E)33.4

Question 37

Calculate the percentage by mass of nitrogen in PtCl₂(NH₃)₂.

A)4.67
B)9.34
C)9.90
D)4.95
E)12.67

Question 38

The mass % of F in the binary compound KrF₂ is ________.

A)18.48
B)45.38
C)68.80
D)81.52
E)31.20

Question 39

Calculate the percentage by mass of ammonia in cisplatin,PtCl₂(NH₃)₂.

A)5.68
B)11.35
C)4.67
D)12.53
E)18.09

Question 40

How many atoms of nitrogen are in 10 g of NH₄NO₃?

A)3.5
B)1.5 × 10²³
C)3.0 × 10²³
D)1.8
E)2

Question 41

How many oxygen atoms are contained in 2.74 g of Al₂(SO₄)₃?

A)12
B)6.02 × 10²³
C)7.22 × 10²⁴
D)5.79 × 10²²
E)8.01 × 10^-3

Question 42

What is the total number of atoms in 0.139 mol of Fe(OH₂)₆³⁺?

A)19.0
B)1.59 × 10²⁴
C)8.37 × 10²²
D)2.64
E)1.84 × 10²⁴

Question 43

One million argon atoms is ________ mol (rounded to two significant figures)of argon atoms.

A)3.0
B)1.7 × 10^-18
C)6.0 × 10²³
D)1.0 × 10^-6
E)1.0 × 10⁺⁶

Question 44

Calculate the percentage by mass of carbon in CO₂.

A)27.29
B)75.10
C)73.05
D)72.71
E)37.53

Question 45

One mole of ________ contains the smallest number of atoms.

A)S₈
B)C₁₀H₈
C)Al₂(SO₄)₃
D)Na₃PO₄
E)NaCl

Question 46

How many molecules of CH₄ are in 48.2 g of this compound?

A)5.00 × 10^-24
B)2.00 × 10²³
C)4.64 × 10²⁶
D)1.81 × 10²⁴
E)4.00

Question 47

Gaseous neon has a density of 0.900 g/L at standard conditions.How many neon atoms are in 1.00 L of neon gas at standard conditions?

A)5.42 × 10²³
B)1.35 × 10²⁵
C)7.41 × 10^-26
D)2.69 × 10²²
E)6.02 × 10²³

Question 48

A 30.5 gram sample of glucose (C₆H₁₂O₆)contains ________ mol of glucose.

A)0.424
B)0.169
C)5.90
D)2.36
E)0.136

Question 49

Which of the following contains the largest number of atoms in mole?

A)S₈
B)C₄H₁₀
C)Al₂(SO₄)₃
D)Na₃PO₄
E)Cl₂

Question 50

A sample of CH₂F₂ with a mass of 19 g contains ________ atoms of F.

A)2.2 × 10²³
B)38
C)3.3 × 10²⁴
D)4.4 × 10²³
E)9.5

Question 51

Calculate the percentage by mass of lead in Pb(NO₃)₂.

A)38.6
B)44.5
C)62.6
D)65.3
E)71.2

Question 52

Calculate the percentage by mass of hydrogen in PtCl₂(NH₃)₂.

A)1.558
B)1.008
C)0.672
D)0.034
E)2.016

Question 53

When the following equation is balanced,the coefficient of H₂ is ________. K (s)+ H₂O (l)→ KOH (aq)+ H₂ (g)

A)1
B)2
C)3
D)4
E)5

Question 54

Propane (C₃H₈)reacts with oxygen in the air to produce carbon dioxide and water.In a particular experiment,38.0 grams of carbon dioxide are produced from the reaction of 22.05 grams of propane with excess oxygen.What is the % yield in this reaction?

A)38.0
B)57.6
C)66.0
D)86.4
E)94.5

Question 55

How many sulfur dioxide molecules are there in 1.80 mol of sulfur dioxide?

A)1.08 × 10²³
B)6.02 × 10²⁴
C)1.80 × 10²⁴
D)1.08 × 10²⁴
E)6.02 × 10²³

Question 56

The molecular formula of aspartame,the generic name of NutraSweet^®,is C₁₄H₁₈N₂O_5.What is the mass (g)of 1.00 mol of aspartame?

A)24
B)156
C)294
D)43
E)39

Question 57

When the following equation is balanced,the coefficient of H₂S is ________. FeCl₃ (aq)+ H₂S (g)→ Fe₂S₃ (s)+ HCl (aq)

A)1
B)2
C)3
D)5
E)4

Question 58

How many carbon atoms are there in 52.06 g of carbon dioxide?

A)5.206 × 10²⁴
B)3.134 × 10²⁵
C)7.122 × 10²³
D)8.648 × 10^-23
E)1.424 × 10²⁴

Question 59

When the following equation is balanced,the coefficient of H₂O is ________. Ca (s)+ H₂O (l)→ Ca(OH)₂ (aq)+ H₂ (g)

A)1
B)2
C)3
D)5
E)4

Question 60

When the following equation is balanced,the coefficients are ________. NH₃ (g)+ O₂ (g)→ NO₂ (g)+ H₂O (g)

A)1, 1, 1, 1
B)4, 7, 4, 6
C)2, 3, 2, 3
D)1, 3, 1, 2
E)4, 3, 4, 3

Question 61

How many oxygen atoms are there in 52.06 g of carbon dioxide?

A)1.424 × 10²⁴
B)6.022 × 10²³
C)7.122 × 10²³
D)5.088 × 10²³
E)1.018 × 10²⁴

Question 62

Which hydrocarbon pair below has identical mass percentage of C?

A)C₃H₄ and C₃H₆
B)C₂H₄ and C₃H₄
C)C₂H₄ and C₄H₂
D)C₂H₄ and C₃H₆
E)none of the above

Question 63

How many grams of sodium carbonate contain 1.773 × 10¹⁷ carbon atoms?

A)3.121 × 10^-5
B)1.011 × 10^-5
C)1.517 × 10^-5
D)9.100 × 10^-5
E)6.066 × 10^-5

Question 64

There are ________ oxygen atoms in 30 molecules of C₂₀H₄₂S₃O₂.

A)6.0 × 10²³
B)1.8 × 10²⁵
C)3.6 × 10²⁵
D)1.2 × 10²⁴
E)60

Question 65

The compound responsible for the characteristic smell of garlic is allicin,C₆H₁₀OS₂.What is the mass (g)of 1.00 mol of allicin?

A)34
B)162
C)86
D)61
E)19

Question 66

When the following equation is balanced,the coefficient of Al₂O₃ is ________. Al₂O₃ (s)+ C (s)+ Cl₂ (g)→ AlCl₃ (s)+ CO (g)

A)1
B)2
C)3
D)4
E)5

Question 67

A nitrogen oxide is 63.65% by mass nitrogen.The molecular formula could be ________.

A)NO
B)NO₂
C)N₂O
D)N₂O₄
E)either NO₂ or N₂O₄

Question 68

A sulfur oxide is 50.0% by mass sulfur.This molecular formula could be ________.

A)SO
B)SO₂
C)S₂O
D)S₂O₄
E)either SO₂ or S₂O₄

Question 69

When the following equation is balanced,the coefficients are ________. Al(NO₃)₃ + Na₂S → Al₂S₃ + NaNO₃

A)2, 3, 1, 6
B)2, 1, 3, 2
C)1, 1, 1, 1
D)4, 6, 3, 2
E)2, 3, 2, 3

Question 70

How many moles of sodium carbonate contain 1.773 × 10¹⁷ carbon atoms?

A)5.890 × 10^-7
B)2.945 × 10^-7
C)1.473 × 10^-7
D)8.836 × 10^-7
E)9.817 × 10^-8

Question 71

How many sulfur dioxide molecules are there in 0.180 mol of sulfur dioxide?

A)1.80 × 10²³
B)6.02 × 10²⁴
C)6.02 × 10²³
D)1.08 × 10²⁴
E)1.08 × 10²³

Question 72

When the following equation is balanced,the coefficient of Al is ________. Al (s)+ H₂O (l)→ Al(OH (s)+ H₂ (g)

A)1
B)2
C)3
D)5
E)4

Question 73

When the following equation is balanced,the coefficient of H₃PO₄ is ________. H₃PO₄ (aq)+ NaOH (aq)→ Na₃PO₄ (aq)+ H₂O (l)

A)1
B)2
C)3
D)4
E)0

Question 74

When the following equation is balanced,the coefficient of C₃H₈O₃ is ________. C₃H₈O₃ (g)+ O₂ (g)→ CO₂ (g)+ H₂O (g)

A)1
B)2
C)3
D)7
E)5

Question 75

When the following equation is balanced,the coefficient of water is ________. K (s)+ H₂O (l)→ KOH (aq)+ H₂ (g)

A)1
B)2
C)3
D)4
E)5

Question 76

When the following equation is balanced,the coefficient of oxygen is ________. PbS (s)+ O₂ (g)→ PbO (s)+ SO₂ (g)

A)1
B)3
C)2
D)4
E)5

Question 77

Write the balanced equation for the reaction that occurs when methanol,CH₃OH (l),is burned in air. What is the coefficient of methanol in the balanced equation?

A)1
B)2
C)3
D)4
E)3/2

Question 78

Balance the following reaction and determine the coefficient of nitric acid. N₂O₅ (g)+ H₂O (l)→ HNO₃ (aq)

A)5
B)2
C)3
D)4
E)1

Question 79

When the following equation is balanced,the coefficient of dinitrogen pentoxide is ________. N₂O₅ (g)+ H₂O (l)→ HNO₃ (aq)

A)1
B)2
C)3
D)4
E)5

Question 80

When the following equation is balanced,the coefficient of sulfur dioxide is ________. PbS (s)+ O₂ (g)→ PbO (s)+ SO₂ (g)

A)5
B)1
C)3
D)2
E)4