Question 1

How many moles of BCl3 are needed to produce 10.0 g of HCl(aq) in the following reaction? 
BCl3(g) + 3H2O(l) → 3HCl(aq) + B(OH)3(aq)

Accepted Answer

A)  0. 0914 mol 
B)  0. 274 mol 
C)  0.823 mol 
D)  10.9 mol 
A)  0. 0914 mol 
B)  0. 274 mol 
C)  0.823 mol 
D)  10.9 mol

Question 2

Balance the following equation:
________ C10H12 + ________ O2 → ________ H2O + ________ CO2

Accepted Answer

C₁₀H₁₂ + 13O₂→

Question 3

Determine the oxidation state of P in PO33-.

Accepted Answer

A)  +3 
B)  +6 
C)  +2 
D)  0 
E)  -3 
A)  +3 
B)  +6 
C)  +2 
D)  0 
E)  -3

Question 4

Sodium metal and water react to form hydrogen and sodium hydroxide. If 5.98 g of sodium react with water to form 0.26 g of hydrogen and 10.40 g of sodium hydroxide, what mass of water was involved in the reaction?

Accepted Answer

A)  4.68 g 
B)  5.98 g 
C)  10.14 g 
D)  10.66 g 
A)  4.68 g 
B)  5.98 g 
C)  10.14 g 
D)  10.66 g

Question 5

How many grams of H2 gas can be produced by the reaction of 54.0 grams of Al(s) with an excess of dilute hydrochloric acid in the reaction shown below? 2Al(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2(g)

Accepted Answer

A)  2.68 g 
B)  4.04 g 
C)  6.05 g 
D)  12.1 g 
A)  2.68 g 
B)  4.04 g 
C)  6.05 g 
D)  12.1 g

Question 6

How many grams of Li3N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 
6Li(s) + N2(g) → 2Li3N(s)

Accepted Answer

A)  18.3 g Li3N 
B)  20.3 g Li3N 
C)  58.3 g Li3N 
D)  61.0 g Li3N 
E)  15.1 g Li3N 
A)  18.3 g Li3N 
B)  20.3 g Li3N 
C)  58.3 g Li3N 
D)  61.0 g Li3N 
E)  15.1 g Li3N

Question 7

What element is undergoing oxidation (if any) in the following reaction? 
Zn(s) + 2AgNO3(aq) → Zn(NO3)2(aq) + 2Ag(s)

Accepted Answer

A)  Zn 
B)  N 
C)  O 
D)  Ag 
E)  This is not an oxidation-reduction reaction. 
A)  Zn 
B)  N 
C)  O 
D)  Ag 
E)  This is not an oxidation-reduction reaction.

Question 8

When 11.0 g of calcium metal is reacted with water, 5.00 g of calcium hydroxide is produced. Using the following balanced equation, calculate the percent yield for the reaction. 
Ca(s) + 2H2O(l) → Ca(OH)2(aq) + H2(g)

Accepted Answer

A)  12.3% 
B)  24.6% 
C)  45.5% 
D)  84.0% 
A)  12.3% 
B)  24.6% 
C)  45.5% 
D)  84.0%

Question 9

Based on the balanced chemical equation shown below, what volume of 0.250 mol L-1 K2S2O3(aq) is needed to completely react with 24.88 mL of 0.125 mol L-1 KI3(aq), according to the following chemical equation: 
2S2O32-(aq) + I3-(aq) → S4O62-(aq) + 3I-(aq)

Accepted Answer

A)  6.22 mL 
B)  12.4 mL 
C)  24.9 mL 
D)  99.5 mL 
A)  6.22 mL 
B)  12.4 mL 
C)  24.9 mL 
D)  99.5 mL

Question 10

Identify the reducing agent in the following redox reaction: 
Zn(s) + 2AgNO3(aq) → Zn(NO3)2(aq) + 2Ag(s)

Accepted Answer

A)  Zn(s) 
B)  Ag+(aq) 
C)  Ag(s) 
D)  NO3-(aq) 
E)  Zn2+(aq) 
A)  Zn(s) 
B)  Ag+(aq) 
C)  Ag(s) 
D)  NO3-(aq) 
E)  Zn2+(aq)

Question 11

What is the concentration of NO3- ions in a solution prepared by dissolving 25.0 g of Ca(NO3)2 in enough water to produce 300. mL of solution?

Accepted Answer

A)  0. 254 mol L-1 
B)  0. 508 mol L-1 
C)  0. 672 mol L-1 
D)  1.02 mol L-1 
A)  0. 254 mol L-1 
B)  0. 508 mol L-1 
C)  0. 672 mol L-1 
D)  1.02 mol L-1

Question 12

When silver nitrate reacts with barium chloride, silver chloride and barium nitrate are formed. How many grams of silver chloride are formed when 10.0 g of silver nitrate reacts with 15.0 g of barium chloride?

Accepted Answer

A)  8.44 g 
B)  9.40 g 
C)  11.9 g 
D)  18.8 g 
A)  8.44 g 
B)  9.40 g 
C)  11.9 g 
D)  18.8 g

Question 13

Calculate the concentration (M) of sodium ions in a solution made by diluting 80.0 mL of a 0.174 mol L-1 solution of sodium sulfide to a total volume of 125 mL.

Accepted Answer

Question 14

Define a salt bridge.

Accepted Answer

A)  A pathway, composed of salt water, that ions pass through. 
B)  A pathway in which no ions flow. 
C)  A pathway between the cathode and anode in which ions are reduced. 
D)  A pathway between the cathode and anode in which ions are oxidized. 
E)  A pathway through which counterions can flow between the half-cells without the solutions in the half-cell totally mixing. 
A)  A pathway, composed of salt water, that ions pass through. 
B)  A pathway in which no ions flow. 
C)  A pathway between the cathode and anode in which ions are reduced. 
D)  A pathway between the cathode and anode in which ions are oxidized. 
E)  A pathway through which counterions can flow between the half-cells without the solutions in the half-cell totally mixing.

Question 15

What are the required coefficients to properly balance the following chemical reaction? H2(g) + Cl2(g) → HCl(g)

Accepted Answer

A)  1, 1, 2 
B)  2, 2,   
C)  1, 1, 1 
D)  2, 1, 2 
E)  1, 2, 1 
A)  1, 1, 2 
B)  2, 2,   
C)  1, 1, 1 
D)  2, 1, 2 
E)  1, 2, 1

Question 16

Based on the balanced chemical equation shown below, determine the mass percent of Fe3+ in a 0.7450 g sample of iron ore if 22.40 mL of a 0.1000 mol L-1 stannous chloride, SnCl2(aq), solution is required to completely react with the Fe3+ present in the ore sample. The chemical equation for the reaction is: 2Fe3+(aq) + Sn2+(aq) → 2Fe2+(aq) + Sn4+(aq)

Accepted Answer

A)  5.365% 
B)  8.396% 
C)  16.79% 
D)  33.58% 
A)  5.365% 
B)  8.396% 
C)  16.79% 
D)  33.58%

Question 17

How many grams of oxygen are formed when 6.21 moles of KOH are formed? 4KO(s) + 2H2O(l) → 4KOH(s) + O2(g)

Accepted Answer

A)  19.9 g O2 
B)  27.9 g O2 
C)  49.7 g O2 
D)  3.59 g O2 
E)  11.7 g O2 
A)  19.9 g O2 
B)  27.9 g O2 
C)  49.7 g O2 
D)  3.59 g O2 
E)  11.7 g O2

Question 18

Determine the oxidation state of Mn in KMnO4.

Accepted Answer

Question 19

Magnesium burns in air with a dazzling brilliance to produce magnesium oxide: 2Mg(s) +   (g) → 2MgO(s)
When 6.00 g of magnesium burns, what is the theoretical yield of magnesium oxide?

Accepted Answer

A)  0.247 g 
B)  19.9 g 
C)  6.00 g 
D)  4.97 g 
E)  9.95 g 
A)  0.247 g 
B)  19.9 g 
C)  6.00 g 
D)  4.97 g 
E)  9.95 g

Question 20

Two samples of calcium fluoride are decomposed into their constituent elements. The first sample produced 0.154 g of calcium and 0.146 g of fluorine. If the second sample produced 294 mg of fluorine, how many grams of calcium were formed?

Accepted Answer

A)  0.280 g 
B)  3.09 × 102 g 
C)  3.13 g 
D)  0.310 g 
E)  2.80 × 102 g 
A)  0.280 g 
B)  3.09 × 102 g 
C)  3.13 g 
D)  0.310 g 
E)  2.80 × 102 g

Exam 4: Chemical Reactions and Stoichiometry

How many moles of BCl3 are needed to produce 10.0 g of HCl(aq) in the following reaction? BCl3(g) + 3H2O(l) → 3HCl(aq) + B(OH)3(aq)

Balance the following equation: ________ C10H12 + ________ O2 → ________ H2O + ________ CO2

Determine the oxidation state of P in PO33-.

Sodium metal and water react to form hydrogen and sodium hydroxide. If 5.98 g of sodium react with water to form 0.26 g of hydrogen and 10.40 g of sodium hydroxide, what mass of water was involved in the reaction?

How many grams of H2 gas can be produced by the reaction of 54.0 grams of Al(s) with an excess of dilute hydrochloric acid in the reaction shown below? 2Al(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2(g)

How many grams of Li3N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 6Li(s) + N2(g) → 2Li3N(s)

What element is undergoing oxidation (if any) in the following reaction? Zn(s) + 2AgNO3(aq) → Zn(NO3)2(aq) + 2Ag(s)

When 11.0 g of calcium metal is reacted with water, 5.00 g of calcium hydroxide is produced. Using the following balanced equation, calculate the percent yield for the reaction. Ca(s) + 2H2O(l) → Ca(OH)2(aq) + H2(g)

Based on the balanced chemical equation shown below, what volume of 0.250 mol L-1 K2S2O3(aq) is needed to completely react with 24.88 mL of 0.125 mol L-1 KI3(aq), according to the following chemical equation: 2S2O32-(aq) + I3-(aq) → S4O62-(aq) + 3I-(aq)

Identify the reducing agent in the following redox reaction: Zn(s) + 2AgNO3(aq) → Zn(NO3)2(aq) + 2Ag(s)

What is the concentration of NO3- ions in a solution prepared by dissolving 25.0 g of Ca(NO3)2 in enough water to produce 300. mL of solution?

When silver nitrate reacts with barium chloride, silver chloride and barium nitrate are formed. How many grams of silver chloride are formed when 10.0 g of silver nitrate reacts with 15.0 g of barium chloride?

Calculate the concentration (M) of sodium ions in a solution made by diluting 80.0 mL of a 0.174 mol L-1 solution of sodium sulfide to a total volume of 125 mL.

Define a salt bridge.

What are the required coefficients to properly balance the following chemical reaction? H2(g) + Cl2(g) → HCl(g)

How many grams of oxygen are formed when 6.21 moles of KOH are formed? 4KO(s) + 2H2O(l) → 4KOH(s) + O2(g)

Determine the oxidation state of Mn in KMnO4.

Magnesium burns in air with a dazzling brilliance to produce magnesium oxide: 2Mg(s) + (g) → 2MgO(s) When 6.00 g of magnesium burns, what is the theoretical yield of magnesium oxide?

Two samples of calcium fluoride are decomposed into their constituent elements. The first sample produced 0.154 g of calcium and 0.146 g of fluorine. If the second sample produced 294 mg of fluorine, how many grams of calcium were formed?

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Molecules, Compounds, and Nomenclature

Gases

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding Ii: Molecular Shapes, Valence Bond Theory, and Molecular Orbital Theory

Liquids, Solids, and Intermolecular Forces

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

Organic Chemistry Ii: Reactions

Biochemistry

Chemistry of the Nonmetals

Metals and Metallurgy

Transition Metals and Coordination Compounds

Filters

How many moles of BCl₃ are needed to produce 10.0 g of HCl(aq) in the following reaction? BCl₃(g) + 3H₂O(l) → 3HCl(aq) + B(OH)₃(aq)

Balance the following equation: C₁₀H₁₂ + O₂→ H₂O + CO₂

Determine the oxidation state of P in PO₃^3-.

How many grams of H₂ gas can be produced by the reaction of 54.0 grams of Al(s) with an excess of dilute hydrochloric acid in the reaction shown below? 2Al(s) + 6HCl(aq) → 2AlCl₃(aq) + 3H₂(g)

How many grams of Li₃N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 6Li(s) + N₂(g) → 2Li₃N(s)

What element is undergoing oxidation (if any) in the following reaction? Zn(s) + 2AgNO₃(aq) → Zn(NO₃)₂(aq) + 2Ag(s)

When 11.0 g of calcium metal is reacted with water, 5.00 g of calcium hydroxide is produced. Using the following balanced equation, calculate the percent yield for the reaction. Ca(s) + 2H₂O(l) → Ca(OH)₂(aq) + H₂(g)

Based on the balanced chemical equation shown below, what volume of 0.250 mol L^-1 K₂S₂O₃(aq) is needed to completely react with 24.88 mL of 0.125 mol L^-1 KI₃(aq), according to the following chemical equation: 2S₂O₃^2-(aq) + I₃^-(aq) → S₄O₆^2-(aq) + 3I^-(aq)

Identify the reducing agent in the following redox reaction: Zn(s) + 2AgNO₃(aq) → Zn(NO₃)₂(aq) + 2Ag(s)

What is the concentration of NO₃^- ions in a solution prepared by dissolving 25.0 g of Ca(NO₃)₂ in enough water to produce 300. mL of solution?

Calculate the concentration (M) of sodium ions in a solution made by diluting 80.0 mL of a 0.174 mol L^-1 solution of sodium sulfide to a total volume of 125 mL.

What are the required coefficients to properly balance the following chemical reaction? H₂(g) + Cl₂(g) → HCl(g)

How many grams of oxygen are formed when 6.21 moles of KOH are formed? 4KO(s) + 2H₂O(l) → 4KOH(s) + O₂(g)

Determine the oxidation state of Mn in KMnO₄.