Deck 5: Chemical Reactions

Question 1

Aspartic acid is an amino acid used to synthesize proteins. What is the molar mass of aspartic acid shown below?

A)121.09 g/mol
B)133.11 g/mol
C)117.0 g/mol
D)126.04 g/mol
E)132.09 g/mol

Answer 1

133.11 g/mol

Question 2

Which chemical equation is properly balanced?

A)SO₂ + O₂ + H₂O → H₂SO₄
B)2 SO₂ + O₂ + 2 H₂O → 2 H₂SO₄
C)SO₂ + O₂ + 4 H₂O → 2 H₂SO₄
D)4 SO₂ + O₂ + 4 H₂O → 4 H₂SO₄

Answer 2

2 SO₂ + O₂ + 2 H₂O → 2 H₂SO₄

Question 3

Identify the correct product that would complete the following double displacement reaction: NaOH + HBr → ___ + H₂O

A)HBr
B)NaH
C)NaBr
D)OBr₂
E)None of the choices are correct.

Answer 3

NaBr

Question 4

What is the mass of 3.81 mol of PH₃?

A)34.0 g
B)3.81 g
C)8.92 g
D)130. g
E)0.112 g

Question 5

How many moles of carbon dioxide are in 211 g of carbon dioxide?

A)929 mol of CO₂
B)4.79 mol of CO₂
C)167 mol of CO₂
D)0.209 mol of CO₂

Question 6

How many moles of chloroethylene (C₂H₃Cl)contain 5.47 × 10²⁶ molecules?

A)3.29 × 10⁵⁰ mol of C₂H₃Cl
B)5.47 × 10²⁶ mol of C₂H₃Cl
C)909 mol of C₂H₃Cl
D)5450 mol of C₂H₃Cl

Question 7

Identify the correct classification for the reaction H₂O + SO₃ → H₂SO₄

A)Combination
B)Decomposition
C)Single Replacement
D)Double Replacement
E)None of the choices are correct.

Question 8

What is the formula weight of Co(NO₃)₃?

A)88.94 amu
B)244.96 amu
C)216.94 amu
D)148.96 amu
E)196.96 amu

Question 9

How many iron atoms are in 0.32 mol of Fe₂O₃?

A)3.9 × 10²³ iron atoms
B)3.9 iron atoms
C)6.02 × 10²³ iron atoms
D)1.9 × 10²³ iron atoms
E)1.1 × 10^-24 iron atoms

Question 10

Complete the following table using the given balanced equation and the initial quantities of reactants. Equation: S₈ + 12 O₂ → 8 SO₃

A)16 molecules formed
B)8 molecules formed
C)32 molecules formed
D)1 molecule formed

Question 11

What is the formula weight of KCl?

A)74.55 amu
B)66.42 amu
C)36.00 amu
D)1386 amu

Question 12

Identify the correct classification for the reaction 2 PbSO₄ → 2 PbSO₃ + O₂

A)Combination
B)Decomposition
C)Single Replacement
D)Double Replacement
E)None of the choices are correct.

Question 13

Complete the following table using the given balanced equation and the initial quantities of reactants. Equation: N₂(g)+ 2 O₂(g)→ 2 NO₂(g)

A)10 molecules formed
B)5 molecules formed
C)12 molecules formed
D)15 molecules formed

Question 14

Which sample contains the largest number of molecules?

A)100 g of CO₂
B)100 g of CH₄
C)100 g of CBr₄
D)100 g of CHBr₃

Question 15

Which reaction is a double displacement reaction?

A)3 Mg + Fe₂O₃ → 2 Fe + 3 MgO
B)2 KBr + Cl₂ → 2 KCl + B^r2
C)2 H₂ + O₂ → 2 H₂O
D)3 Ca(OH)₂ + Al₂(SO₄)₃ → 3 CaSO₄ + 2 Al(OH)₃

Question 16

The Greek letter delta (Δ)may be written over the reaction arrow in a chemical equation to indicate that ________.

A)heat is generated when the reaction occurs
B)a catalyst is needed for the reaction to occur
C)water is needed for the reaction to occur
D)heat is needed for the reaction to occur

Question 17

In the chemical equation 2 Co(NO₃)₃ + 3 (NH₄)₂S → Co₂S₃ + 6 NH₄NO₃ ,how many nitrogen atoms are on each side of the equation?

A)2
B)3
C)6
D)12
E)16

Question 18

The law of conservation of mass states that ________.

A)atoms cannot be created or destroyed in a chemical reaction
B)molecules cannot be created or destroyed in a chemical reaction
C)compounds cannot be created or destroyed in a chemical reaction
D)heat cannot be created or destroyed in a chemical reaction

Question 19

How many carbon atoms are in 3.85 mol of carbon?

A)3.85 carbon atoms
B)23.2 carbon atoms
C)6.02 × 10²³ carbon atoms
D)2.32 × 10²⁴ carbon atoms
E)6.40 × 10^-24 carbon atoms

Question 20

Write a balanced chemical equation for the reaction of acetone (C₃H₆O)with oxygen (O₂)to form carbon dioxide (CO₂)and water (H₂O).

A)C₃H₆O + O₂ → CO₂ + H₂O
B)C₃H₆O + 4 O₂ → 3 CO₂ + 3 H₂O
C)3 CO₂ + 3 H₂O → C₃H₆O + 4 O₂
D)6 C₃H₆O + 8 O₂ → 6 CO₂ + 6 H₂O

Question 21

Consider the oxidation of sodium metal to sodium oxide described by the balanced equation: 4 Na + O₂ → 2 Na₂O. If 2.55 mol of sodium reacts,and 75.0 g of Na₂O is produced,what is the percent yield?

A)94.9% yield
B)34.0% yield
C)47.5% yield
D)190.% yield

Question 22

The molecules A and B react according to the following chemical equation: A + 2B → C. Identify the limiting reactant under the reaction conditions shown in the molecular art below. A = large white circles B = small grey circles

A)A is the limiting reactant
B)B is the limiting reactant
C)Both A and B are the limiting reactants
D)Neither A nor B are the limiting reactants

Question 23

How many moles of sulfur trioxide are formed from 3 moles of oxygen using the given balanced equation? 2 SO₂ + O₂ → 2 SO₃

A)1 mol of SO₃
B)2 mol of SO₃
C)3 mol of SO₃
D)5 mol of SO₃
E)6 mol of SO₃

Question 24

What are the two half reactions that show how many electrons are gained or lost by each species in the reaction: Ni²⁺(aq)+ Mg(s)→ Ni(s)+ Mg²⁺(aq)?

A)Ni²⁺(aq)+ e^- → Ni(s)and Mg(s)→ Mg²⁺(aq)+ e^-
B)Ni²⁺(aq)+ 2 e^- → Ni(s)and Mg(s)→ Mg²⁺(aq)+ 2 e^-
C)Ni²⁺(aq)→ Ni(s)+ 2 e^- and Mg(s)+ 2 e^- → Mg²⁺(aq)
D)Ni²⁺(aq)→ Ni(s)+ e^- and Mg(s)+ e^- → Mg²⁺(aq)
E)Ni²⁺(aq)+ 2 e^- → Ni(s)and Mg(s)+ 2 e^- → Mg²⁺(aq)

Question 25

Tin (II)fluoride can be made by the following reaction: Sn(s)+ 2 HF(g)→ SnF₂(s)+ H₂(g). What is the maximum amount of SnF₂ that can be produced when 0.480 moles of Sn are mixed with 0.720 moles of HF?

A)0.360 moles of SnF₂
B)0.480 moles of SnF₂
C)0.600 moles of SnF₂
D)0.720 moles of SnF₂
E)1.20 moles of SnF₂

Question 26

A balanced chemical equation tells the number of ________ of each reactant that combine and the number of ________ of each product formed.

A)grams; grams
B)grams; moles
C)moles; grams
D)moles; moles

Question 27

Consider the mixture of Cl₂ and F₂ in a closed container as illustrated below. What will the contents of the container look like if the molecules undergo the reaction: Cl₂(g)+ 3 F₂(g)→ 2 ClF₃(g)?

A)
B)
C)
D)

Question 28

If a synthesis has four steps and each step has a 75% yield (0.75 written as a decimal),what is the overall percent yield?

A)75%
B)19%
C)56%
D)32%
E)42%

Question 29

How many moles of sodium chloride (table salt,NaCl,molar mass 58.44 g/mol)are contained in a 1.00 lb box of table salt?

A)26,500 mol of NaCl
B)4.68 × 10²⁴ mol of NaCl
C)58.44 mol NaCl
D)7.77 mol of NaCl
E)0.129 mol of NaCl

Question 30

In the balanced redox reaction: 2 C₂H₆(g)+ 7 O₂(g)→ 4 CO₂(g)+ 6 H₂O(g),which species is reduced?

A)C₂H₆(g)
B)O₂(g)
C)CO₂(g)
D)H₂O(g)

Question 31

How many moles of sulfur trioxide are formed from 3 moles of sulfur dioxide using the given balanced equation? 2 SO₂ + O₂ → 2 SO₃

A)1 mol of SO₃
B)2 mol of SO₃
C)3 mol of SO₃
D)5 mol of SO₃
E)6 mol of SO₃

Question 32

Suppose the theoretical yield in a reaction is 10.5 g and the percent yield is 75.5%. What is the actual yield of product obtained?

A)793 g
B)7.93 g
C)13.9 g
D)0.139 g

Question 33

The molecules A and B react according to the following chemical equation: A + B → C. Identify the limiting reactant under the reaction conditions shown in the molecular art below. A = large grey circles B = small black circles

A)A is the limiting reactant
B)B is the limiting reactant
C)Both A and B are the limiting reactants
D)Neither A nor B are the limiting reactants

Question 34

In the balanced redox reaction: 2 C₂H₆(g)+ 7 O₂(g)→ 4 CO₂(g)+ 6 H₂O(g),which species is oxidized?

A)C₂H₆(g)
B)O₂(g)
C)CO₂(g)
D)H₂O(g)

Question 35

Which quantity has the greatest mass?

A)2.0 mol of Na
B)2.0 mol of Na₂O
C)2.0 mol of NaCl
D)2.0 mol of O₂
E)All of these quantities have the same mass.

Question 36

Consider the reaction: 2 Al(OH)₃ + 3 H₂SO₄ → Al₂(SO₄)₃ + 6 H₂O. How many grams of Al₂(SO₄)₃ are generated when 152 g of H₂SO₄ reacts?

A)530. g of Al₂(SO₄)₃
B)1590 g of Al₂(SO₄)₃
C)177 g of Al₂(SO₄)₃
D)43.6 g of Al₂(SO₄)₃
E)131 g of Al₂(SO₄)₃

Question 37

Potassium metal (K)reacts violently when added to water according to the balanced equation: 2 K(s)+ 2 H₂O(l)→ 2 KOH(aq)+ H₂(g). How many moles of H₂O are needed to react completely with 7.54 mol of K?

A)2 mol of H₂O
B)7.54 mol of H₂O
C)15.1 mol of H₂O
D)3.77 mol of H₂O

Question 38

In the balanced redox reaction: 2 Cu(s)+ S(s)→ Cu₂S(s),how many electrons are gained or lost by each copper atom?

A)Each copper atom gains two (2)electrons
B)Each copper atom gains one (1)electron
C)Each copper atom loses one (1)electron
D)Each copper atom loses two (2)electrons

Question 39

Identify the species that is oxidized and the species that is reduced in the reaction: 2 I^- + Cl₂ → 2 Cl^- + I₂.

A)I^- is oxidized and Cl₂ is reduced.
B)Cl₂ is oxidized and I^- is reduced.
C)I₂ is oxidized and Cl^- is reduced.
D)Cl₂ is oxidized and Cl^- is reduced.
E)I₂ is oxidized and I^- is reduced.

Question 40

Consider the oxidation of sodium metal to sodium oxide described by the balanced equation: 4 Na + O₂ → 2 Na₂O. What is the theoretical yield of Na₂O in grams from 9.0 mol of O₂?

A)11 g of Na₂O
B)410 g of Na₂O
C)1,100 g of Na₂O
D)280 g of Na₂O
E)560 g of Na₂O

Question 41

Beaker A contains 1 mole of iron atoms,and Beaker B contains 1 mole of lead atoms. Which statement concerning these two samples is known with certainty?

A)Beakers A and B contain samples with the same molar mass.
B)Beakers A and B contain an equal number of atoms.
C)Beakers A and B contain an equal volume of atoms.
D)Beakers A and B contain equal masses of atoms.

Question 42

All chemical reactions convert one substance into another.

Question 43

How many grams of oxygen gas are required to completely react with 77.28 g of ethane (C₂H₆)in the balanced redox reaction: 2 C₂H₆(g)+ 7 O₂(g)→ 4 CO₂(g)+ 6 H₂O(g)?

A)77.28 g of O₂(g)
B)23.50 g of O₂(g)
C)143.9 g of O₂(g)
D)8.995 g of O₂(g)
E)287.8 g of O₂(g)

Question 44

One mole of oxygen molecules contains more atoms than one mole of lead atoms.

Question 45

In calculating the percent yield,both the actual yield and theoretical yield must be in units of grams.

Question 46

Blimps are essentially very large helium filled balloons. If a blimp contains 536 kg of helium,how many helium atoms are present inside the blimp?

A)134,000 He atoms
B)8.9 x 10^-19 He atoms
C)8.06 x 10²⁸ He atoms
D)3.23 x 10²⁶ He atoms

Question 47

Sodium fluoride can be produced from the reaction between sodium metal and fluorine gas. Which of the following represents the balanced chemical equation for this reaction?

A)2 Na(s)+ F₂(g)→ 2 NaF(s)
B)Na⁺(s)+ F^-(g)→ NaF(s)
C)Na(s)+ F₂(g)→ NaF₂(s)
D)2 Na(s)+ F₂(g)→ Na₂F₂(s)

Question 48

A student runs the reaction: LiOH + CO₂ → LiHCO₃. The reaction consumes 45.0 g LiOH and produces 72.8 g of LiHCO₃. Which of the statements concerning this reaction is true?

A)The actual yield of the product is 72.8 g LiHCO₃.
B)The theoretical yield of the product is 72.8 g LiHCO₃.
C)The theoretical yield of the product is 117.8 g LiHCO₃.
D)The percent yield of the reaction is 61.8%.

Question 49

How many carbon atoms are in 77.28 g of ethane (C₂H₆)?

A)2.570 carbon atoms
B)5.140 carbon atoms
C)3.094 × 10²⁴ carbon atoms
D)1.548 × 10²⁴ carbon atoms
E)1.238 × 10²⁵ carbon atoms

Question 50

What is the molar mass of the compound show below?

A)90.13 amu
B)90.13 g/mol
C)93.13 amu
D)93.13 g/mol
E)91.14 g/mol

Question 51

A chemical equation is balanced by adding coefficients in front of some formulas so that the number of atoms of each element is equal on both sides of the equation.

Question 52

What is the mass of 3.4 × 10²⁰ molecules of ethanol (C₂H₆O)expressed in milligrams?

A)0.026 mg of ethanol
B)26,000 mg of ethanol
C)0.012 mg of ethanol
D)26 mg of ethanol

Question 53

The molar mass of CaCO₃ is greater than the molar mass of Ca(NO₃)₂.

Question 54

The chemical equation: KClO₃(s)→ KCl(s)+ O₂(g)is not balanced. Balance this equation,then select the statement that best describes the balanced equation.

A)The balanced equation will have six atoms of oxygen on each side of the equation.
B)The balanced equation will have one atom of chlorine on each side of the equation.
C)The balanced equation will have an O₃ on the product side of the equation.
D)The balanced equation will have a coefficient of 1 in front of KCl.

Question 55

Oxidation is the gain of electrons by an atom.

Question 56

The subscripts in chemical formulas are changed in order to balance a chemical equation.

Question 57

The conversion factor shown below was obtained from the balanced chemical equation: 4 KO₂(s)+ 2 CO₂(g)→ 2 K₂CO₃(s)+ 3 O₂(g). This conversion factor would be used to calculate which of the following?

A)The amount of KO₂ required to react with a certain amount of O₂
B)The amount of O₂ that can react with a certain amount of KO₂
C)The amount of O₂ that can be produced from a certain amount of KO₂
D)The amount of KO₂ that is required to produce a certain amount of O₂

Question 58

Assume that the mixture of substances in Figure 1 undergoes a chemical reaction. Which diagram represents a product mixture that is consistent with the Law of Conservation of Mass?

A)
B)
C)
D)It is impossible to predict based on the information given.

Question 59

The actual yield is the amount of product expected from a given amount of reactant based on the coefficients in the balanced chemical equation.

Question 60

A mole of copper atoms has more atoms than a mole of lead atoms.

Question 61

The formula weight of a compound is the sum of the atomic weights of all the atoms in a compound,reported in atomic mass units.

Question 62

The reaction: Mg(s)+ 2 HBr(aq)→ MgBr₂(s)+ H₂(g)is an oxidation-reduction reaction.

Question 63

The actual yield of a product in a chemical reaction should not exceed its theoretical yield.

Question 64

In the reaction: Ni²⁺(aq)+ Mg(s)→ Ni(s)+ Mg²⁺(aq),two electrons are transferred from Ni² to Mg.

Question 65

In redox reactions,metals tend to undergo oxidation.

Question 66

2 Co(NO₃)₃(aq)+ 3 (NH₄)₂S(aq)→ Co₂S₃(s)+ 3 NH₄NO₃(aq)is a properly balanced chemical equation.

Question 67

In the reaction: Ni²⁺(aq)+ Mg(s)→ Ni(s)+ Mg²⁺(aq),the species that undergoes reduction is Mg(s).

Question 68

The balanced reaction: 4 NO₂ + O₂ + 2 H₂O → 4 HNO₃ states that four grams of nitrogen dioxide reacts with each gram of oxygen.

Question 69

In a chemical reaction,the actual yield of a product may be reduced by side reactions.

Question 70

A mole is a quantity that contains 6.02 × 10^-23 atoms,molecules,or ions.

Question 71

In the reaction: Ni²⁺(aq)+ Mg(s)→ Ni(s)+ Mg²⁺(aq),the oxidizing agent is Ni²⁺(aq).

Question 72

The electric current generated in batteries used for portable electronic devices and pacemakers results from redox reactions.

Question 73

Consider the balanced reaction: 4 NO₂ + O₂ + 2 H₂O → 4 HNO₃. If 100. g of NO₂ is placed in a reaction vessel the theoretical yield of nitric acid (HNO₃)collected will be 137 g.

Question 74

The balanced reaction: 4 NO₂ + O₂ + 2 H₂O → 4 HNO₃ states that four moles of nitrogen dioxide react with each mole of oxygen.

Question 75

The balanced reaction: 4 Fe(s)+ 3 O₂(g)→ 2 Fe₂O₃(s)is an oxidation-reduction reaction.

Question 76

Consider the balanced reaction: 2 A + B → C,where the molar mass of B is less than the molar mass of A. It requires a smaller mass of A to completely react with given mass of B.

Question 77

When the mass of a substance produced in a reaction must be calculated,first its number of moles is determined using mole ratios,and then Avogadro's number is used to convert moles to grams.

Question 78

A 100-g sample of the compound below contains greater than one mole of molecules.

Question 79

Combustion reactions are redox reactions.

Question 80

To determine the overall percent yield in a synthesis that has more than one step,subtract the percent yield for each step from 100% yield.