Deck 6: Chemical Reactions and Quantities

Question 1

Which of the following is an oxidation-reduction reaction?

A) CaCl₂ + Na2SO₄ → CaSO₄ + 2NaCl
B) KOH + HNO₃ → H₂O + KNO₃
C) N₂ + O₂ → 2NO
D) AgNO₃ + NaCl → AgCl + NaNO₃
E) Al₄(SO₄)3 + 6KOH → 2 Al(OH)3 + 3K₂SO₄

Answer 1

N₂ + O₂ → 2NO

Question 2

What coefficient is placed in front of O₂ to complete the balancing of the following equation? C5H₈ + ? O₂ → 5CO₂ + 4H₂O

A) 1
B) 3
C) 5
D) 7
E) 9

Answer 2

7

Question 3

The reaction of carbon with oxygen to produce carbon monoxide is an example of which class of reaction? 2C(s) + O₂ (g) → 2CO(g)

A) single replacement
B) double replacement
C) combination
D) catalytic
E) endothermic

Answer 3

combination

Question 4

In the following reaction, when the equation is correctly balanced, what is the correct coefficient for sodium chloride? Pb(NO₃)₂(aq) + NaCl(aq) → PbCl₂ (s) + NaNO₃(aq)

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

Question 5

What is the coefficient of hydrogen, H₂, when the following equation is balanced? Al + H₂SO₄ → Al₂(SO₄)₃ + ? H₂

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

Question 6

In the following reaction, when the equation is correctly balanced, what is the correct coefficient for aluminum chloride? Al(s) + Cl₂(g) → AlCl₃(s)

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

Question 7

Pentane (C₅H₁₂) reacts with oxygen (O₂) to form carbon dioxide (CO₂) and water (H₂O) according to the following reaction. Answer the question(s) that follow about this reaction.
C₅H₁₂ + ? O₂ → ? CO₂ + ? H₂O
What is the coefficient for water in the balanced equation?

A) 2
B) 4
C) 5
D) 6
E) 8

Question 8

Pentane (C₅H₁₂) reacts with oxygen (O₂) to form carbon dioxide (CO₂) and water (H₂O) according to the following reaction. Answer the question(s) that follow about this reaction.
C₅H₁₂ + ? O₂ → ? CO₂ + ? H₂O
What is the coefficient for carbon dioxide in the balanced equation?

A) 2
B) 4
C) 5
D) 6
E) 8

Question 9

In the following reaction, when the equation is correctly balanced, what is the correct coefficient for H₂? Fe(s) + HCl(aq) → FeCl₃(aq) + H₂ (g)

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

Question 10

What is oxidized and what is reduced in the following reaction? 2Al(s) + 3Br₂ (g) → 2AlBr₃(s)

A) Al is oxidized and Br₂ is reduced.
B) AlBr₃ is reduced and Br₂ is oxidized.
C) Al is reduced and Br₂ is oxidized.
D) AlBr₃ is reduced and Al is oxidized.
E) AlBr3 is oxidized and Al is reduced.

Question 11

What is the classification for this unbalanced reaction? Fe + HCl → FeCl₃ + H₂

A) dehydration
B) combination
C) decomposition
D) single replacement
E) double replacement

Question 12

In this reaction, what is the coefficient for calcium oxide? CaO(s) + CO₂(g) → CaCO₃(s)

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

Question 13

Pentane (C₅H₁₂) reacts with oxygen (O₂) to form carbon dioxide (CO₂) and water (H₂O) according to the following reaction. Answer the question(s) that follow about this reaction.
C₅H₁₂ + ? O₂ → ? CO₂ + ? H₂O
What is the coefficient for oxygen in the balanced equation?

A) 2
B) 4
C) 5
D) 6
E) 8

Question 14

The following reaction takes place when an electric current is passed through water. It is an example of a __________ reaction. 2 H₂O → 2H₂ + O₂

A) combination
B) single replacement
C) dehydration
D) decomposition
E) double replacement

Question 15

Which of the following gives the balanced equation for this reaction? K₃PO₄ + Ca(NO₃)₂ → Ca₃(PO₄)₂ + KNO₃

A) KPO₄ + CaNO₃ + KNO₃
B) K₃PO₄ + Ca(NO₃)₂→ Ca₃(PO₄)₂ + 3KNO₃
C) 2K₃PO₄ + Ca(NO₃)₂ → Ca₃(PO₄)₂ + 6KNO₃
D) 2K₃PO₄ + 3Ca(NO₃)₂ → Ca₃(PO₄)₂ + 6KNO₃
E) K₃PO₄ + Ca(NO₃)₂ → Ca₃(PO₄)₂ + KNO₃

Question 16

Which of the following correctly gives the best coefficients for the reaction below? N₂H4 + H₂O₂ → N₂ + H₂O

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

Question 17

What is the classification for this reaction? SO₃ (g) + H₂O (l) → H₂SO₄ (l)

A) decomposition
B) combination
C) replacement
D) double replacement
E) oxidation reduction

Question 18

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.

Question 19

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.

Question 20

In a __________ reaction, two or more elements or compounds form one product.

A) decomposition
B) single replacement
C) dehydration
D) double replacement
E) combination

Question 21

What is the molar mass of sucrose (C₁₂H₂₂O₁₁)?

A) 29.0 g
B) 50.2 g
C) 210 g
D) 342 g
E) 182 g

Question 22

In an oxidation-reduction reaction, the substance oxidized always

A) takes on oxygen atoms.
B) shows a loss of electrons.
C) gives up hydrogen atoms.
D) shows a gain of electrons.
E) becomes a charged species.

Question 23

Which of the following describes an oxidation reaction?

A) loss of electrons or loss of oxygen
B) loss of electrons or gain of oxygen
C) loss of electrons or gain of hydrogen
D) gain of electrons or gain of oxygen
E) gain of electrons or loss of H

Question 24

0.100 mole of lithium weighs

A) 3.00 g.
B) 0.300 g.
C) 6.94 g.
D) 0.694 g.
E) 0.700 g.

Question 25

What is the molar mass of copper(II) sulfate, CuSO₄?

A) 16.0 g
B) 63.6 g
C) 111.6 g
D) 159.6 g
E) 319.2 g

Question 26

In this reaction, what is the substance oxidized? Zn(s) + 2 HCl(aq) → ZnCl₂(aq) + H₂(g)

A) chlorine
B) zinc chloride
C) hydrogen
D) zinc
E) oxygen

Question 27

Calculate the molar mass of magnesium chloride, MgCl₂.

A) 24.3 g
B) 95.2 g
C) 125.9 g
D) 59.8 g
E) 70.0 g

Question 28

Calculate the molar mass of potassium chloride, KCl.

A) 74.6 g
B) 54.5 g
C) 6.74 g
D) 67.4 g
E) 19.0 g

Question 29

One mole of particles of any substance contains how many particles?

A) 10⁶
B) 3 × 10^-10
C) 3 × 10¹⁰
D) 6.02 × 10²³
E) 6.02 × 10^-23

Question 30

One mole of neon atoms has a mass of

A) 6.02 × 1023 grams.
B) 14.0 g.
C) 10.0 g.
D) 20.2 g.
E) 30.2 g.

Question 31

How many moles of carbon atoms are there in 0.500 mole of C₂H₆?

A) 0.500 moles
B) 1.00 moles
C) 3.00 moles
D) 6.02 × $10^{23}$ moles
E) 4.00 moles

Question 32

How many moles of iron are present in 3.15 × 10²⁴ atoms of iron?

A) 5.23 moles
B) 1.90 moles
C) 292 moles
D) 0.523 moles
E) 1.90 × 10⁴⁸ moles

Question 33

How many moles of water, H₂O, are present in 75.0 g of H₂O?

A) 4.41 moles
B) 4.17 moles
C) 75.0 moles
D) 7.50 moles
E) 1.35 × 103 moles

Question 34

How many molecules of water, H₂O, are present in 75.0 g of H₂O?

A) 75.0 molecules
B) 4.17 molecules
C) 7.53 × 10²⁴ molecules
D) 2.51 × 10²⁴ molecules
E) 5.02 × 10²⁴ molecules

Question 35

The molar mass of potassium is

A) 19 g.
B) 31.0 g.
C) 6.02 × 10²³ grams.
D) 39.1 g.
E) 15g.

Question 36

In an oxidation-reduction reaction, the substance reduced always

A) takes on oxygen atoms.
B) shows a loss of electrons.
C) gives up hydrogen atoms.
D) shows a gain of electrons.
E) becomes a charged species.

Question 37

How many hydrogen atoms are present in 75.0 of g H₂O?

A) 75.0 atoms
B) 4.17 atoms
C) 7.53 × 10²⁴ atoms
D) 2.51 × 10²⁴ atoms
E) 5.02 × 10²⁴ atoms

Question 38

What is the molar mass of sodium phosphate, Na3PO₄?

A) 119.0 g
B) 308.0 g
C) 164.0 g
D) 226.0 g
E) 354.0 g

Question 39

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 × 1023 grams of an element.
E) moles in 6.02 × 1023 amu of an element.

Question 40

One mole of helium gas weighs

A) 1.00 g.
B) 2.00 g.
C) 3.00 g.
D) 4.00 g.
E) 8.00 g.

Question 41

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
When 36.0 g of H₂O react, how many grams of NH3 are produced?

A) 34.0 g
B) 10.0 g
C) 5.67 g
D) 11.3 g
E) 102 g

Question 42

For the question(s) that follow, consider the following equation.
2Mg + O₂ → 2MgO
In the reaction of nitrogen gas, N₂, with hydrogen gas, H₂, to form ammonia gas, NH3 , how many moles of hydrogen are needed to react with two moles of nitrogen?

A) 2 moles
B) 4 moles
C) 6 moles
D) 8 moles
E) 10 moles

Question 43

How many grams of glucose (C6H12O6) are in 3.55 moles of glucose?

A) 180. g
B) 639 g
C) 103 g
D) 426 g
E) 50.7 g

Question 44

For the question(s) that follow, consider the following equation.
2Mg + O₂ → 2MgO
How many grams of MgO are produced when 40.0 grams of O₂ react completely with Mg?

A) 30.4 g
B) 50.4 g
C) 60.8 g
D) 101 g
E) 201 g

Question 45

For the question(s) that follow, consider the following balanced equation.
Mg?N?(s) + 6H?O(l) ? 3Mg(OH)?(s) + 2NH₃(g)

-What is the correct form of the conversion factor needed to convert the number of moles of H?O to the number of moles of NH₃ produced?

A) $\frac { 2 \text { moles of } \mathrm { NH } _ { 3 } } { 6 \text { moles of } \mathrm { H } _ { 2 } \mathrm { O } }$
B) $\frac { 6 \text { moles of } \mathrm { H } _ { 2 } \mathrm { O } } { 2 \text { moles of } \mathrm { NH } _ { 3 } }$
C) $\frac { 1 \text { mole of } \mathrm { Mg } _ { 3 } \mathrm {~N} _ { 2 } } { 6 \text { moles of } \mathrm { H } _ { 2 } \mathrm { O } }$
D) $\frac { 18 g \text { of } \mathrm { H } _ { 2 } \mathrm { O } } { 1 \text { mole of } \mathrm { H } _ { 2 } \mathrm { O } }$
E) $\frac { 18 g \text { of } \mathrm { H } _ { 2 }O } { 17 \mathrm {~g} \text { of } \mathrm { NH } _ { 3 } }$

Question 46

The molar mass of C₃H₈O₂ is

A) 76.0 g.
B) 60.0 g.
C) 29.0 g.
D) 69.0 g.
E) 52.0 g.

Question 47

The molar mass of calcium hydroxide, Ca(OH)₂, is

A) 58.1 g.
B) 57.1 g.
C) 74.1 g.
D) 114.2 g.
E) 38.0 g.

Question 48

For the question(s) that follow, consider the following equation.
2Mg + O₂ → 2MgO
The number of moles of MgO produced when 0.20 mole of O₂ reacts completely is

A) 0.10 mole.
B) 0.20 mole.
C) 0.40 mole.
D) 0.60 mole.
E) 0.80 mole.

Question 49

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.

Question 50

What is the molar mass of Mg₃(PO₄)₂, a substance formerly used in medicine as an antacid?

A) 71.3 g
B) 118.3 g
C) 150.3 g
D) 214.3 g
E) 262.9 g

Question 51

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
How many grams of H₂O are needed to produce 150 g of Mg(OH)₂?

A) 46 g
B) 18 g
C) 130 g
D) 93 g
E) 23 g

Question 52

How many grams of Fe2O₃ are there in 0.500 mole of Fe2O₃?

A) 79.8 g
B) 35.9 g
C) 63.8 g
D) 51.9 g
E) 160. g

Question 53

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
How many grams of hydrogen are needed to produce 1.80 g of water according to this equation? 2H₂ + O₂ → 2H₂O

A) 0.100 g
B) 0.180 g
C) 0.200 g
D) 2.00 g
E) 4.00 g

Question 54

For the question(s) that follow, consider the following equation.
2Mg + O₂ → 2MgO
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.

Question 55

How many moles of K2SO₄ are in 15.0 g of K2SO₄?

A) 0.172 moles
B) 2.61 × 103 moles
C) 0.111 moles
D) 0.0861 moles
E) 0.119 moles

Question 56

For the question(s) that follow, consider the following equation.
2Mg + O₂ → 2MgO
How many moles of magnesium are needed to react with 0.50 mole of O₂?

A) 0.50 mole
B) 1.0 moles
C) 2.0 moles
D) 3.0 moles
E) 4.0 moles

Question 57

For the question(s) that follow, consider the following equation.
2Mg + O₂ → 2MgO
When 4 moles of aluminum are allowed to react with an excess of chlorine gas, Cl₂, how many moles of aluminum chloride are produced?

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

Question 58

3.00 moles of NO₂ have a mass of

A) 138 g.
B) 46.0 g.
C) 30.0 g.
D) 90.0 g.
E) 45.0 g.

Question 59

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
When 2 moles of Mg₃N₂ are allowed to react, how many moles of H₂O also react?

A) 1 mole
B) 4 moles
C) 6 moles
D) 8 moles
E) 12 moles

Question 60

Given the following equation, what is the correct form of the conversion factor needed to convert the number of moles of O? to the number of moles of Fe₂O? produced?
4Fe(s) + 3O? (g) ? 2Fe₂O?(s)

A) $\frac { 4 \text { moles of } \mathrm { F } _ { \mathrm { e } } } { 3 \text { moles of } \mathrm { O } _ { 2 } }$
B) $\frac { 4 \text { moles of } \mathrm { F } _ { \mathrm { e } } } { 3 \text { moles of } \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 } }$
C) $\frac { 3 \text { moles of } \mathrm { O } _ { 2 } } { 3 \text { moles of } \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 } }$
D) $\frac { 2 \text { moles of } \mathrm { Fe } _ { \mathrm { 2 } } \mathrm { O } _ { 3 } } { 4 \text { moles of Fe} }$

E) $\frac { 2 \text { moles of } \mathrm { Fe } _ { 2 } \mathrm { O } _ { 3 } } { 3 \text { moles of } \mathrm { O } _ { 2 } }$

Question 61

In an endothermic reaction,

A) heat flows out of the system.
B) energy is absorbed by the system.
C) the temperature of the system increases.
D) the products have less energy that the reactants.
E) the products have the same energy that the reactants.

Question 62

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
How many grams of CO₂ are produced from 125 g of O₂ and excess CH4? CH4 + 2O₂ → CO₂ + 2H₂O

A) 125 g of CO₂
B) 62.5 g of CO₂
C) 172 g of CO₂
D) 85.9 g of CO₂
E) 250. g of CO₂

Question 63

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
When 85.0 g of CH4 are mixed with 160. g of O₂ the limiting reactant is __________. CH4 + 2O₂ → CO₂ + 2H₂O

A) CH4
B) O₂
C) CO₂
D) H₂O

Question 64

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

Question 65

What type of reaction is: CH4 + 2O₂ → CO₂ + 2H₂O + 218 kcal?

A) an endothermic reaction
B) an exothermic reaction
C) a single replacement reaction
D) a combination reaction
E) a decomposition reaction

Question 66

When 85.0 g of CH4 are mixed with 160. g of O₂ what is the maximum amount of CO₂ that can be produced? CH4 + 2O₂ → CO₂ + 2H₂O

A) 2.50 moles
B) 5.00 moles
C) 5.31 moles
D) 7.81 moles

Question 67

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
Find the mass of AlCl3 that is produced when 10.0 grams of Al2O₃ react with 10.0 g of HCl according to the following equation. Al2O₃(s) + 6HCl(aq) → 2AlCl3(aq) + 3H₂O(aq)

A) 16.2 g
B) 20.0 g
C) 12.2 g
D) 10.0 g
E) 6.10 g

Question 68

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
When 3.05 moles of CH4 are mixed with 5.03 moles of O₂ the limiting reactant is __________. CH4 + 2O₂ → CO₂ + 2H₂O

A) CH4
B) O₂
C) CO₂
D) H₂O

Question 69

Any reaction that absorbs 150 kcal of energy can be classified as __________.

A) endothermic
B) exothermic
C) activated
D) reduction
E) oxidation

Question 70

How many kcal are produced when 32.0 g of CH4 react? CH4 + 2O₂ → CO₂ + 2H₂O + 218 kcal

A) 218 kcal
B) 109 kcal
C) 436 kcal
D) 6.81 kcal
E) 698 kcal

Question 71

When 10.0 g of NH3 reacts, the actual yield of N₂ is 8.50 g. What is the percent yield? 4NH3 (g) + 6NO(g) → 5N₂ (g) + 6H₂O(l)

A) 85.0%
B) 51.5%
C) 20.6%
D) 41.3%
E) 8.5%

Question 72

If the reaction shown below is exothermic, the energy level of the reactants is __________. H₂ + O₂ → 2N₂O

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

Question 73

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

Question 74

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
How many grams of NO are required to produce 145 g of N₂ in the following reaction? 4NH3(g) + 6NO(g) → 5N₂ (g) + 6H₂O(l)

A) 186 g
B) 155 g
C) 125 g
D) 129 g
E) 145 g

Question 75

For the reaction: 2H₂O(l) + 137 kcal → 2H₂ (g) + O₂ (g) how many kcal are needed to react 50.0 g H₂O(l)?

A) 380. kcal
B) 137 kcal
C) 274 kcal
D) 190. kcal
E) 760. kcal

Question 76

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
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. AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)

A) 107.9 g
B) 169.9 g
C) 84.4 g
D) 0.589 g
E) 58.9 g

Question 77

For the question(s) that follow, consider the following balanced equation.
Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH3(g)
Find the mass of AlCl3 that is produced when 25.0 grams of Al2O₃ react with excess HCl according to the following equation. Al2O₃(s) + 6HCl(aq) → 2AlCl3(aq) + 3H₂O(l)

A) 155 g
B) 72.9 g
C) 65.4 g
D) 32.6 g
E) 16.3 g

Question 78

For the reaction: 2H₂O(l) + 137 kcal → 2H₂ (g) + O₂ (g) how many kcal are needed to form 2.00 moles O₂ (g)?

A) 68.5 kcal
B) 137 kcal
C) 274 kcal
D) 190. kcal
E) 548 kcal

Question 79

In this reaction, what is the correct coefficient for hydrogen gas? ? H₂ + ? O₂ → ? H₂O

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

Question 80

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