Question 1

If the percent yield is 82.0%,how many grams of silicon is needed to make 105 g of chromium by the reaction: 3 Si (s)+ 2 Cr2O3 (s)→ 3 SiO2 (s)+ 4 Cr (l)?

Accepted Answer

A) 51.9 g 
B) 92.2 g 
C) 42.5 g 
D) 34.9 g 
E) 13.0 g 
A) 51.9 g 
B) 92.2 g 
C) 42.5 g 
D) 34.9 g 
E) 13.0 g

Question 2

What is the concentration of FeCl3 in a solution prepared by dissolving 20.0 g of FeCl3 in enough water to make 275 mL of solution?

Accepted Answer

A) 4.48 × 10-4 mol L-1 
B) 0.448 mol L-1 
C) 2.23 mol L-1 
D) 2.23 × 103 mol L-1 
A) 4.48 × 10-4 mol L-1 
B) 0.448 mol L-1 
C) 2.23 mol L-1 
D) 2.23 × 103 mol L-1

Question 3

What is the sum of the coefficients when the following is balanced with the smallest integer coefficients?
KClO3(s)→ KCl(s)+ O2(g)

Accepted Answer

A) 11 
B) 10 
C) 5 
D) 7 
E) 6 
A) 11 
B) 10 
C) 5 
D) 7 
E) 6

Question 4

In a chemical equation,Δ above the yield sign means the reaction will produce heat.

Accepted Answer

A) True 
 B)False

Question 5

How many grams of CaCl2 are formed when 15.00 mL of 0.00237 mol L-1 Ca(OH)2(aq)reacts with excess Cl2 gas?
2 Ca(OH)2(aq)+ 2 Cl2(g)→ Ca(OCl)2(aq)+ CaCl2(s)+ 2 H2O(l)

Accepted Answer

A) 0.00197 g 
B) 0.00394 g 
C) 0.00789 g 
D) 0.0507 g 
A) 0.00197 g 
B) 0.00394 g 
C) 0.00789 g 
D) 0.0507 g

Question 6

24.0 g of ethane (C2H6)are burned to form CO2 and H2O.How many grams of CO2 are produced?

Accepted Answer

A) 32.8 g 
B) 14.4 g 
C) 43.2 g 
D) 35.1 g 
E) 70.3 g 
A) 32.8 g 
B) 14.4 g 
C) 43.2 g 
D) 35.1 g 
E) 70.3 g

Question 7

45.8 mL of a 3.14 M sodium chloride solution were used to react completely with 50.0 mL of an aqueous silver nitrate solution.What is the molarity of the silver nitrate solution?

Accepted Answer

A) 2.88 M 
B) 1.50 M 
C) 3.14 M 
D) 3.42 M 
E) 1.71 M 
A) 2.88 M 
B) 1.50 M 
C) 3.14 M 
D) 3.42 M 
E) 1.71 M

Question 8

There are ________ mol of bromide ions in 0.900 L of a 0.500 mol L-1 solution of Al Br3 (aq).

Accepted Answer

Question 9

Which of the following processes could theoretically produce the maximum mass of oxygen per gram of metal salt reactant?

Accepted Answer

A) 2 KClO3 → 2 KCl + 3 O2  
B) 4 KO2 + 2 CO2 → 2 K2CO3 + 3 O2  
C) 2 Na2O2 + 2 H2SO4 → 2 H2O + O2  
D) 2 HgO → 2 Hg + O2  
E) NaBrO2 → NaBr + O2  
A) 2 KClO3 → 2 KCl + 3 O2  
B) 4 KO2 + 2 CO2 → 2 K2CO3 + 3 O2  
C) 2 Na2O2 + 2 H2SO4 → 2 H2O + O2  
D) 2 HgO → 2 Hg + O2  
E) NaBrO2 → NaBr + O2

Question 10

What volume of a 0.540 mol L-1 NaOH(aq)solution contains 11.5 g of NaOH?

Accepted Answer

A) 0.155 L 
B) 0.532 L 
C) 1.88 L 
D) 6.44 L 
A) 0.155 L 
B) 0.532 L 
C) 1.88 L 
D) 6.44 L

Question 11

When 7.00 × 1022 molecules of ammonia react with 6.00 × 1022 molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced?
4 NH3(g)+ 3 O2(g)→ 2 N2(g)+ 6 H2O(g)

Accepted Answer

A) 1.63 g 
B) 1.86 g 
C) 4.19 g 
D) 6.51 g 
A) 1.63 g 
B) 1.86 g 
C) 4.19 g 
D) 6.51 g

Question 12

Write the complete balanced equation for the complete combustion reaction expected to occur between C3H7OH and O2.

Accepted Answer

A) C3H7OH + O2 → 3 CO2 + 4 H2O 
B) 3 C3H7OH + 9 O2 → 6 CO2 + 8 H2O + 3 C 
C) 2 C3H7OH + 6 O2 → CO + 8 H2O 
D) 2 C3H7OH + 9 O2 → 6 CO2 + 8 H2O 
E) 2 C3H7OH + 9 O2 → 6 C + 8 H2 + 10 O2  
A) C3H7OH + O2 → 3 CO2 + 4 H2O 
B) 3 C3H7OH + 9 O2 → 6 CO2 + 8 H2O + 3 C 
C) 2 C3H7OH + 6 O2 → CO + 8 H2O 
D) 2 C3H7OH + 9 O2 → 6 CO2 + 8 H2O 
E) 2 C3H7OH + 9 O2 → 6 C + 8 H2 + 10 O2

Question 13

How many grams of N2 are required to react with 2.30 moles of Mg in the following process?
3 Mg + N2 → Mg3N2? (Mg = 24.3 g/mol,N = 14.0 g/mol)

Accepted Answer

A) 21.5 g 
B) 0.767 g 
C) 64.4 g 
D) 0.027 g 
E) 193.2 g 
A) 21.5 g 
B) 0.767 g 
C) 64.4 g 
D) 0.027 g 
E) 193.2 g

Question 14

Sulfuric acid can be prepared by a multistep process summarized as:
2 SO2 + O2 + 2 H2O → 2 H2SO4 
What mass of sulfuric acid could be produced daily by a process using 38 kg per day of sulfur dioxide with a 70% conversion efficiency ("yield"),assuming that sulfur dioxide is the limiting reagent?

Accepted Answer

A) 27 kg/day 
B) 41 kg/day 
C) 54 kg/day 
D) 58 kg/day 
E) 83 kg/day 
A) 27 kg/day 
B) 41 kg/day 
C) 54 kg/day 
D) 58 kg/day 
E) 83 kg/day

Question 15

How much Cl2,in g,is required to produce 12.0 g CCl4 according to the following reaction?

Accepted Answer

A) 12.0 g 
B) 5.52 g 
C) 22.1 g 
D) 1.38 g 
E) 11.0 g 
A) 12.0 g 
B) 5.52 g 
C) 22.1 g 
D) 1.38 g 
E) 11.0 g

Question 16

Chromium in its +VI oxidation state is considered a hazardous,carcinogenic species,destruction of which may be accomplished by the process symbolized as:
4 Zn + K2Cr2O7 + 7 H2SO4 → 4 ZnSO4 + 2 CrSO4 + K2SO4 + 7 H2O
If 1.0 mol of each reactant is mixed,what is the limiting reagent,and what is the theoretical yield in moles of chromium(II)sulfate?

Accepted Answer

A) limiting reagent Zn,0.50 mol chromium(II)sulfate 
B) limiting reagent K2Cr2O7,2.0 mol chromium(II)sulfate 
C) limiting reagent H2SO4,0.29 mol chromium(II)sulfate 
D) limiting reagent H2,1.0 mol chromium(II)sulfate 
E) no limiting reagent,1.0 mol chromium(II)sulfate 
A) limiting reagent Zn,0.50 mol chromium(II)sulfate 
B) limiting reagent K2Cr2O7,2.0 mol chromium(II)sulfate 
C) limiting reagent H2SO4,0.29 mol chromium(II)sulfate 
D) limiting reagent H2,1.0 mol chromium(II)sulfate 
E) no limiting reagent,1.0 mol chromium(II)sulfate

Question 17

How many millilitres of a 9.0 mol L-1 H2SO4(aq)solution are needed to make 0.35 L of a 3.5 mol L-1 solution?

Accepted Answer

A) 0.14 mL 
B) 0.90 mL 
C) 140 mL 
D) 900 mL 
A) 0.14 mL 
B) 0.90 mL 
C) 140 mL 
D) 900 mL

Question 18

Lithium and nitrogen react in a combination reaction to produce lithium nitride:
6 Li(s)+ N2(g)→ 2Li3N(s)
How many moles of lithium are needed to produce 0.60 mol of Li3N when the reaction is carried out in the presence of excess nitrogen?

Accepted Answer

A) 0.30 
B) 1.8 
C) 0.20 
D) 0.40 
E) 3.6 
A) 0.30 
B) 1.8 
C) 0.20 
D) 0.40 
E) 3.6

Question 19

What is the sum of the coefficients when the following is balanced with the smallest integer coefficients?
CaC2(s)+ H2O(l)→ Ca(OH)2(s)+ C2H2(g)

Accepted Answer

A) 8 
B) 4 
C) 5 
D) 10 
E) 9 
A) 8 
B) 4 
C) 5 
D) 10 
E) 9

Question 20

How many grams of sulfuric acid,H2SO4,can be obtained from 578 grams of iron ore if the ore is 76.0% by mass FeS? The reactions involved are given below.Each reaction is 92.0% efficient.
4 FeS + 7O2 → 2 Fe2O3 + 4 SO2
2 SO2 + O2 → 2 SO3
SO3 + H2O → H2SO4

Accepted Answer

A) 502 g 
B) 307 g 
C) 382 g 
D) 95.5 g 
E) 629 g 
A) 502 g 
B) 307 g 
C) 382 g 
D) 95.5 g 
E) 629 g

Exam 4: Chemical Reactions

If the percent yield is 82.0%,how many grams of silicon is needed to make 105 g of chromium by the reaction: 3 Si (s)+ 2 Cr2O3 (s)→ 3 SiO2 (s)+ 4 Cr (l)?

What is the concentration of FeCl3 in a solution prepared by dissolving 20.0 g of FeCl3 in enough water to make 275 mL of solution?

What is the sum of the coefficients when the following is balanced with the smallest integer coefficients? KClO3(s)→ KCl(s)+ O2(g)

In a chemical equation,Δ above the yield sign means the reaction will produce heat.

How many grams of CaCl2 are formed when 15.00 mL of 0.00237 mol L-1 Ca(OH)2(aq)reacts with excess Cl2 gas? 2 Ca(OH)2(aq)+ 2 Cl2(g)→ Ca(OCl)2(aq)+ CaCl2(s)+ 2 H2O(l)

24.0 g of ethane (C2H6)are burned to form CO2 and H2O.How many grams of CO2 are produced?

45.8 mL of a 3.14 M sodium chloride solution were used to react completely with 50.0 mL of an aqueous silver nitrate solution.What is the molarity of the silver nitrate solution?

There are ________ mol of bromide ions in 0.900 L of a 0.500 mol L-1 solution of Al Br3 (aq).

Which of the following processes could theoretically produce the maximum mass of oxygen per gram of metal salt reactant?

What volume of a 0.540 mol L-1 NaOH(aq)solution contains 11.5 g of NaOH?

When 7.00 × 1022 molecules of ammonia react with 6.00 × 1022 molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH3(g)+ 3 O2(g)→ 2 N2(g)+ 6 H2O(g)

Write the complete balanced equation for the complete combustion reaction expected to occur between C3H7OH and O2.

How many grams of N2 are required to react with 2.30 moles of Mg in the following process? 3 Mg + N2 → Mg3N2? (Mg = 24.3 g/mol,N = 14.0 g/mol)

Sulfuric acid can be prepared by a multistep process summarized as: 2 SO2 + O2 + 2 H2O → 2 H2SO4 What mass of sulfuric acid could be produced daily by a process using 38 kg per day of sulfur dioxide with a 70% conversion efficiency ("yield"),assuming that sulfur dioxide is the limiting reagent?

How much Cl2,in g,is required to produce 12.0 g CCl4 according to the following reaction?

How many millilitres of a 9.0 mol L-1 H2SO4(aq)solution are needed to make 0.35 L of a 3.5 mol L-1 solution?

Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6 Li(s)+ N2(g)→ 2Li3N(s) How many moles of lithium are needed to produce 0.60 mol of Li3N when the reaction is carried out in the presence of excess nitrogen?

What is the sum of the coefficients when the following is balanced with the smallest integer coefficients? CaC2(s)+ H2O(l)→ Ca(OH)2(s)+ C2H2(g)

How many grams of sulfuric acid,H2SO4,can be obtained from 578 grams of iron ore if the ore is 76.0% by mass FeS? The reactions involved are given below.Each reaction is 92.0% efficient. 4 FeS + 7O2 → 2 Fe2O3 + 4 SO2 2 SO2 + O2 → 2 SO3 SO3 + H2O → H2SO4

Matter: Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Valence Bond and Molecular Orbital Theories

Intermolecular Forces: Liquids and Solids

Spontaneous Change: Entropy and Gibbs Energy

Solutions and Their Physical Properties

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acidbase Equilibria

Solubility and Complex-Ion Equilibria

Electrochemistry

Chemical Kinetics

Chemistry of the Main-Group Elements I: Groups 1,2,13,and 14

Chemistry of the Main-Group Elements Ii: Groups 18,17,16,15,and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

If the percent yield is 82.0%,how many grams of silicon is needed to make 105 g of chromium by the reaction: 3 Si (s)+ 2 Cr₂O₃(s)→ 3 SiO₂(s)+ 4 Cr (l)?

What is the concentration of FeCl₃ in a solution prepared by dissolving 20.0 g of FeCl₃ in enough water to make 275 mL of solution?

What is the sum of the coefficients when the following is balanced with the smallest integer coefficients? KClO₃(s)→ KCl(s)+ O₂(g)

How many grams of CaCl₂ are formed when 15.00 mL of 0.00237 mol L^-1 Ca(OH)₂(aq)reacts with excess Cl₂ gas? 2 Ca(OH)₂(aq)+ 2 Cl₂(g)→ Ca(OCl)₂(aq)+ CaCl₂(s)+ 2 H₂O(l)

24.0 g of ethane (C₂H₆)are burned to form CO₂ and H₂O.How many grams of CO₂ are produced?

There are ________ mol of bromide ions in 0.900 L of a 0.500 mol L^-1 solution of Al Br₃ (aq).

What volume of a 0.540 mol L^-1 NaOH(aq)solution contains 11.5 g of NaOH?

When 7.00 × 10²² molecules of ammonia react with 6.00 × 10²² molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH₃(g)+ 3 O₂(g)→ 2 N₂(g)+ 6 H₂O(g)

Write the complete balanced equation for the complete combustion reaction expected to occur between C₃H₇OH and O₂.

How many grams of N₂ are required to react with 2.30 moles of Mg in the following process? 3 Mg + N₂ → Mg₃N₂? (Mg = 24.3 g/mol,N = 14.0 g/mol)

How much Cl₂,in g,is required to produce 12.0 g CCl₄ according to the following reaction?

How many millilitres of a 9.0 mol L^-1 H₂SO₄(aq)solution are needed to make 0.35 L of a 3.5 mol L^-1 solution?

Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6 Li(s)+ N₂(g)→ 2Li₃N(s) How many moles of lithium are needed to produce 0.60 mol of Li₃N when the reaction is carried out in the presence of excess nitrogen?

What is the sum of the coefficients when the following is balanced with the smallest integer coefficients? CaC₂(s)+ H₂O(l)→ Ca(OH)₂(s)+ C₂H₂(g)

How many grams of sulfuric acid,H₂SO₄,can be obtained from 578 grams of iron ore if the ore is 76.0% by mass FeS? The reactions involved are given below.Each reaction is 92.0% efficient. 4 FeS + 7O₂ → 2 Fe₂O₃ + 4 SO₂ 2 SO₂ + O₂ → 2 SO₃ SO₃ + H₂O → H₂SO₄