Question 1

Of the following, the only empirical formula is

Accepted Answer

A)  C6H12. 
B)  C4H8. 
C)  C3H14. 
D)  H2O2. 
E)  O3. 
A)  C6H12. 
B)  C4H8. 
C)  C3H14. 
D)  H2O2. 
E)  O3.

Question 2

What volume of 0.742 M Na2CO3 solution contains 44.9 g of Na2CO3?

Accepted Answer

A)  0.314 L 
B)  6.41 × 103 L 
C)  0.571 L 
D)  3.53 × 103 L 
E)  1.75 L 
A)  0.314 L 
B)  6.41 × 103 L 
C)  0.571 L 
D)  3.53 × 103 L 
E)  1.75 L

Question 3

How many moles of sulfate ions are there in a 0.650-L solution of 0.312 M Al2(SO4)3?

Accepted Answer

A)  0.203 mol 
B)  0.608 mol 
C)  6.25 mol 
D)  0.0676 mol 
E)  1.44 mol 
A)  0.203 mol 
B)  0.608 mol 
C)  6.25 mol 
D)  0.0676 mol 
E)  1.44 mol

Question 4

What mass of Na2CO3 is present in 0.700 L of a 0.396 M Na2CO3 solution?

Accepted Answer

A)  29.4 g 
B)  74.2 g 
C)  42.0 g 
D)  187 g 
E)  60.0 g 
A)  29.4 g 
B)  74.2 g 
C)  42.0 g 
D)  187 g 
E)  60.0 g

Question 5

Pure copper may be produced by the reaction of copper(I) sulfide with oxygen gas as follows: 
Cu2S(s) + O2(g) → 2Cu(s) + SO2(g)
What mass of copper(I) sulfide is required in order to prepare 0.750 kg of copper metal?

Accepted Answer

A)  0.750 kg 
B)  0.375 kg 
C)  0.564 kg 
D)  1.88 kg 
E)  0.939 kg 
A)  0.750 kg 
B)  0.375 kg 
C)  0.564 kg 
D)  1.88 kg 
E)  0.939 kg

Question 6

The reaction of HCl with NaOH is represented by the equation 
HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)
What volume of 0.614 M HCl is required to titrate 18.8 mL of 0.619 M NaOH?

Accepted Answer

A)  7.15 mL 
B)  1.63 mL 
C)  19.0 mL 
D)  18.8 mL 
E)  18.6 mL 
A)  7.15 mL 
B)  1.63 mL 
C)  19.0 mL 
D)  18.8 mL 
E)  18.6 mL

Question 7

What mass of iron can be produced from the reaction of 175 kg Fe2O3 with 385 kg CO? 
Fe2O3(s) + 3 CO(g) → 2 Fe(s) + 3 CO2(g)

Accepted Answer

A)  2.19 kg 
B)  30.6 kg 
C)  61.2 kg 
D)  122 kg 
E)  512 kg 
A)  2.19 kg 
B)  30.6 kg 
C)  61.2 kg 
D)  122 kg 
E)  512 kg

Question 8

A solution of sodium oxalate (Na2C2O4) in acidic solution is titrated with a solution of potassium permanganate (KMnO4) according to the following balanced chemical equation: 
2KMnO4(aq) + 8H2SO4(aq) + 5Na2C2O4(aq) → 2MnSO4(aq) + 8H2O(l) + 10CO2(g) + 5Na2SO4(aq) + K2SO4(aq)
What volume of 0.0206 M KMnO4 is required to titrate 0.176 g of Na2C2O4 dissolved in 50.0 mL of solution?

Accepted Answer

A)  3.42 mL 
B)  8.54 mL 
C)  25.5 mL 
D)  63.8 mL 
E)  50.0 mL 
A)  3.42 mL 
B)  8.54 mL 
C)  25.5 mL 
D)  63.8 mL 
E)  50.0 mL

Question 9

How many grams of dioxygen are required to completely burn 4.7 g of C2H5OH?

Accepted Answer

A)  11 g 
B)  16 g 
C)  3.3 g 
D)  45 g 
E)  57 g 
A)  11 g 
B)  16 g 
C)  3.3 g 
D)  45 g 
E)  57 g

Question 10

A certain compound has a molar mass of 210 g/mol. Which of the following is a possible empirical formula for this compound?

Accepted Answer

A)  CH2O 
B)  CHO 
C)  C2H2O2 
D)  C2HO 
E)  C2H2O 
A)  CH2O 
B)  CHO 
C)  C2H2O2 
D)  C2HO 
E)  C2H2O

Question 11

Complete combustion of a 0.70-mol sample of a hydrocarbon, CxHy, gives 2.80 mol of CO2 and 3.50 mol of H2O. The molecular formula of the original hydrocarbon is

Accepted Answer

A)  C2H8. 
B)  C4H10. 
C)  C8H14. 
D)  C5H5. 
E)  C4H6. 
A)  C2H8. 
B)  C4H10. 
C)  C8H14. 
D)  C5H5. 
E)  C4H6.

Question 12

A mass of 0.4113 g of an unknown acid, HA, is titrated with sodium hydroxide, NaOH. If the acid reacts with 28.10 mL of 0.1055 M aqueous sodium hydroxide, what is the molar mass of the acid?

Accepted Answer

A)  2.965 × 10-3 g/mol 
B)  9.128 g/mol 
C)  138.7 g/mol 
D)  337.3 g/mol 
E)  820.7 g/mol 
A)  2.965 × 10-3 g/mol 
B)  9.128 g/mol 
C)  138.7 g/mol 
D)  337.3 g/mol 
E)  820.7 g/mol

Question 13

A 1.078 g sample of a compound containing only carbon, hydrogen, and oxygen is burned in an excess of dioxygen, producing 2.451 g CO2 and 1.003 g H2O. What mass of oxygen is contained in the original sample?

Accepted Answer

A)  0.2970 g 
B)  0.3531 g 
C)  1.373 g 
D)  1.447 g 
E)  0.07480 g 
A)  0.2970 g 
B)  0.3531 g 
C)  1.373 g 
D)  1.447 g 
E)  0.07480 g

Question 14

When strongly heated, boric acid breaks down to boric oxide and water. What mass of boric oxide is formed from the decomposition of 15.0 g of boric acid, B(OH)3? 
2 B(OH)3(s) → B2O3(s) + 3 H2O(g)

Accepted Answer

A)  7.50 g 
B)  15.0 g 
C)  8.44 g 
D)  16.9 g 
E)  33.8 g 
A)  7.50 g 
B)  15.0 g 
C)  8.44 g 
D)  16.9 g 
E)  33.8 g

Question 15

2 Al(s) + 6 HCl(aq) ? 2 AlCl3(aq) + 3 H2(g)
 According to the equation above, what mass of aluminum is needed to completely react with 2.98 mol of hydrochloric acid?

Accepted Answer

A)  241 g 
B)  36.3 g 
C)  26.8 g 
D)  2.98 g 
E)  80.4 g 
A)  241 g 
B)  36.3 g 
C)  26.8 g 
D)  2.98 g 
E)  80.4 g

Question 16

An unknown diprotic acid (H2A) requires 31.81 mL of 0.109 M NaOH to completely neutralize a 0.685 g sample. Calculate the approximate molar mass of the acid.

Accepted Answer

A)  577 g/mol 
B)  395 g/mol 
C)  198 g/mol 
D)  99 g/mol 
E)  288 g/mol 
A)  577 g/mol 
B)  395 g/mol 
C)  198 g/mol 
D)  99 g/mol 
E)  288 g/mol

Question 17

Sulfur dioxide will react with water to form sulfurous acid (see balanced equation below). 
SO2(g) + H2O(l) → H2SO3(l)
What mass of sulfur dioxide is needed to prepare 37.11 g of H2SO3(l)?

Accepted Answer

A)  28.96 g 
B)  47.55 g 
C)  0.5793 g 
D)  0.4521 g 
E)  37.11 g 
A)  28.96 g 
B)  47.55 g 
C)  0.5793 g 
D)  0.4521 g 
E)  37.11 g

Question 18

A 5.95-g sample of AgNO3 is reacted with excess BaCl2 according to the equation 
2AgNO3(aq) + BaCl2(aq) → 2AgCl(s) + Ba(NO3)2(aq)
To give 3.57 g of AgCl. What is the percent yield of AgCl?

Accepted Answer

A)  47.4 % 
B)  35.6 % 
C)  71.1 % 
D)  60.0 % 
E)  100 % 
A)  47.4 % 
B)  35.6 % 
C)  71.1 % 
D)  60.0 % 
E)  100 %

Question 19

Nitric oxide, NO, is made from the oxidation of NH3 as follows: 
4NH3 + 5O2 → 4NO + 6H2O If 9.0-g of NH3 gives 12.0 g of NO, 
what is the percent yield of NO?

Accepted Answer

A)  87 % 
B)  47 % 
C)  13 % 
D)  76 % 
E)  25 % 
A)  87 % 
B)  47 % 
C)  13 % 
D)  76 % 
E)  25 %

Question 20

One step in the isolation of pure rhodium metal (Rh) is the precipitation of rhodium(III) hydroxide from a solution containing rhodium(III) sulfate according to the following balanced chemical equation: 
Rh2(SO4)3(aq) + 6NaOH(aq) → 2Rh(OH)3(s) + 3Na2SO4(aq)
If 3.10 g of rhodium(III) sulfate reacts with excess sodium hydroxide, what mass of rhodium(III) hydroxide may be produced?

Accepted Answer

A)  1.93 g 
B)  6.20 g 
C)  3.10 g 
D)  0.483 g 
E)  3.86 g 
A)  1.93 g 
B)  6.20 g 
C)  3.10 g 
D)  0.483 g 
E)  3.86 g

Exam 5: Stoichiometry: Quantitative Information About Chemical Reactions

Of the following, the only empirical formula is

What volume of 0.742 M Na2CO3 solution contains 44.9 g of Na2CO3?

How many moles of sulfate ions are there in a 0.650-L solution of 0.312 M Al2(SO4)3?

What mass of Na2CO3 is present in 0.700 L of a 0.396 M Na2CO3 solution?

Pure copper may be produced by the reaction of copper(I) sulfide with oxygen gas as follows: Cu2S(s) + O2(g) → 2Cu(s) + SO2(g) What mass of copper(I) sulfide is required in order to prepare 0.750 kg of copper metal?

The reaction of HCl with NaOH is represented by the equation HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l) What volume of 0.614 M HCl is required to titrate 18.8 mL of 0.619 M NaOH?

What mass of iron can be produced from the reaction of 175 kg Fe2O3 with 385 kg CO? Fe2O3(s) + 3 CO(g) → 2 Fe(s) + 3 CO2(g)

How many grams of dioxygen are required to completely burn 4.7 g of C2H5OH?

A certain compound has a molar mass of 210 g/mol. Which of the following is a possible empirical formula for this compound?

Complete combustion of a 0.70-mol sample of a hydrocarbon, CxHy, gives 2.80 mol of CO2 and 3.50 mol of H2O. The molecular formula of the original hydrocarbon is

A mass of 0.4113 g of an unknown acid, HA, is titrated with sodium hydroxide, NaOH. If the acid reacts with 28.10 mL of 0.1055 M aqueous sodium hydroxide, what is the molar mass of the acid?

A 1.078 g sample of a compound containing only carbon, hydrogen, and oxygen is burned in an excess of dioxygen, producing 2.451 g CO2 and 1.003 g H2O. What mass of oxygen is contained in the original sample?

When strongly heated, boric acid breaks down to boric oxide and water. What mass of boric oxide is formed from the decomposition of 15.0 g of boric acid, B(OH)3? 2 B(OH)3(s) → B2O3(s) + 3 H2O(g)

2 Al(s) + 6 HCl(aq) ? 2 AlCl3(aq) + 3 H2(g) According to the equation above, what mass of aluminum is needed to completely react with 2.98 mol of hydrochloric acid?

An unknown diprotic acid (H2A) requires 31.81 mL of 0.109 M NaOH to completely neutralize a 0.685 g sample. Calculate the approximate molar mass of the acid.

Sulfur dioxide will react with water to form sulfurous acid (see balanced equation below). SO2(g) + H2O(l) → H2SO3(l) What mass of sulfur dioxide is needed to prepare 37.11 g of H2SO3(l)?

A 5.95-g sample of AgNO3 is reacted with excess BaCl2 according to the equation 2AgNO3(aq) + BaCl2(aq) → 2AgCl(s) + Ba(NO3)2(aq) To give 3.57 g of AgCl. What is the percent yield of AgCl?

Nitric oxide, NO, is made from the oxidation of NH3 as follows: 4NH3 + 5O2 → 4NO + 6H2O If 9.0-g of NH3 gives 12.0 g of NO, what is the percent yield of NO?

Basic Concepts of Chemistry

Lets Review: the Tools of Quantitative Chemistry

Atoms, Molecules, and Ions

Chemical Reactions

Principles of Chemical Reactivity: Energy and Chemical Reactions

The Structure of Atoms

The Structure of Atoms and Periodic Trends

Bonding and Molecular Structure

Bonding and Molecular Structure Orbital Hybridization and Molecular Orbitals

Gases and Their Properties

Intermolecular Forces and Liquids

The Solid State

Solutions and Their Behavior

Chemical Kinetics: the Rates of Chemical Reactions

Principles of Chemical Reactivity: Equilibria

Principles of Chemical Reactivity: the Chemistry of Acids and Bases

Principles of Chemical Reactivity: Other Aspects of Aqueous Equilibria

Principles of Chemical Reactivity: Entropy and Free Energy

Principles of Chemical Reactivity: Electron Transfer Reactions

Environmental Chemistry: Earths Environment, Energy, and Sustainability

The Chemistry of the Main Group Elements

The Chemistry of the Transition Elements

Carbon: Not Just Another Element

Biochemistry

Nuclear Chemistry

Filters

What volume of 0.742 M Na₂CO₃ solution contains 44.9 g of Na₂CO₃?

How many moles of sulfate ions are there in a 0.650-L solution of 0.312 M Al₂(SO₄)₃?

What mass of Na₂CO₃ is present in 0.700 L of a 0.396 M Na₂CO₃ solution?

Pure copper may be produced by the reaction of copper(I) sulfide with oxygen gas as follows: Cu₂S(s) + O₂(g) → 2Cu(s) + SO₂(g) What mass of copper(I) sulfide is required in order to prepare 0.750 kg of copper metal?

The reaction of HCl with NaOH is represented by the equation HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l) What volume of 0.614 M HCl is required to titrate 18.8 mL of 0.619 M NaOH?

What mass of iron can be produced from the reaction of 175 kg Fe₂O₃ with 385 kg CO? Fe₂O₃(s) + 3 CO(g) → 2 Fe(s) + 3 CO₂(g)

How many grams of dioxygen are required to completely burn 4.7 g of C₂H₅OH?

Complete combustion of a 0.70-mol sample of a hydrocarbon, C_xH_y, gives 2.80 mol of CO₂ and 3.50 mol of H₂O. The molecular formula of the original hydrocarbon is

A 1.078 g sample of a compound containing only carbon, hydrogen, and oxygen is burned in an excess of dioxygen, producing 2.451 g CO₂ and 1.003 g H₂O. What mass of oxygen is contained in the original sample?

When strongly heated, boric acid breaks down to boric oxide and water. What mass of boric oxide is formed from the decomposition of 15.0 g of boric acid, B(OH)₃? 2 B(OH)₃(s) → B₂O₃(s) + 3 H₂O(g)

2 Al(s) + 6 HCl(aq) ? 2 AlCl₃(aq) + 3 H₂(g) According to the equation above, what mass of aluminum is needed to completely react with 2.98 mol of hydrochloric acid?

An unknown diprotic acid (H₂A) requires 31.81 mL of 0.109 M NaOH to completely neutralize a 0.685 g sample. Calculate the approximate molar mass of the acid.

Sulfur dioxide will react with water to form sulfurous acid (see balanced equation below). SO₂(g) + H₂O(l) → H₂SO₃(l) What mass of sulfur dioxide is needed to prepare 37.11 g of H₂SO₃(l)?

A 5.95-g sample of AgNO₃ is reacted with excess BaCl₂ according to the equation 2AgNO₃(aq) + BaCl₂(aq) → 2AgCl(s) + Ba(NO₃)₂(aq) To give 3.57 g of AgCl. What is the percent yield of AgCl?

Nitric oxide, NO, is made from the oxidation of NH₃ as follows: 4NH₃ + 5O₂ → 4NO + 6H₂O If 9.0-g of NH₃ gives 12.0 g of NO, what is the percent yield of NO?