Question 1

The specific heat capacity of methane gas is 2.20 J g-1k-1.How many joules of heat are needed to raise the temperature of 5.00 g of methane from 36.0 °C to 75.0 °C?

Accepted Answer

A) 88.6 J 
B) 429 J 
C) 1221 J 
D) 0.0113 J 
E) 22.9 J 
A) 88.6 J 
B) 429 J 
C) 1221 J 
D) 0.0113 J 
E) 22.9 J

Question 2

The specific heat capacity of liquid water is 4.184 J g-1k-1.How many joules of heat are needed to raise the temperature of 6.00 g of water from 36.0 °C to 75.0 °C?

Accepted Answer

A) 56.0 J 
B) 978 J 
C) 2.78 ×   J 
D) 1.79 ×   J 
E) 52.3 J 
A) 56.0 J 
B) 978 J 
C) 2.78 ×   J 
D) 1.79 ×   J 
E) 52.3 J

Question 3

Cyclohexanol,C6H12O,has a heat of combustion of -890.7 kcal/mol.A sample containing 0.708 g of cyclohexanol undergoes complete combustion in a bomb calorimeter that has a heat capacity of 2.70 kcal/ °C.What is the final temperature if the initial water temperature is 27.0 °C?

Accepted Answer

A) 24.7 °C 
B) 29.3 °C 
C) 27.4 °C 
D) 26.6 °C 
E) 31.4 °C 
A) 24.7 °C 
B) 29.3 °C 
C) 27.4 °C 
D) 26.6 °C 
E) 31.4 °C

Question 4

For the reaction H2(g)+ 1/2 O2(g)→ H2O(g)ΔrH° = -241.8 kJ/mol,
What quantity of heat is liberated by the reaction of 10.0 L of O2 measured at 22.0 °C and 742 mmHg?

Accepted Answer

A) 120 kJ 
B) 2610 kJ 
C) 1310 kJ 
D) 195 kJ 
E) 97.5 kJ 
A) 120 kJ 
B) 2610 kJ 
C) 1310 kJ 
D) 195 kJ 
E) 97.5 kJ

Question 5

A 5.00 g sample of liquid water at 25.0 °C is heated by the addition of 145 J of energy.The final temperature of the water is ________ °C.The specific heat capacity of liquid water is

Accepted Answer

A) 146 
B) 25.1 
C) -18.1 
D) 31.9 
E) 6.94 
A) 146 
B) 25.1 
C) -18.1 
D) 31.9 
E) 6.94

Question 6

The maximum amount of work is provided by a reversible process because equilibrium between the system and the surroundings is always maintained.

Accepted Answer

A) True 
 B)False

Question 7

A certain reaction releases 10.1 kJ at constant volume and at constant pressure releases 8.4 kJ.What is △U for the reaction?

Accepted Answer

A) -10.1 kJ 
B) -8.4 kJ 
C) +8.4 kJ 
D) -1.7 kJ 
A) -10.1 kJ 
B) -8.4 kJ 
C) +8.4 kJ 
D) -1.7 kJ

Question 8

A system that absorbs heat is an exothermic system.

Accepted Answer

A) True 
 B)False

Question 9

When 1.50 mol of CH4(g)reacts with excess Cl2(g)at constant pressure according to the chemical equation shown below,1062 kJ of heat are released.Calculate the value of ΔH for this reaction,as written.
2 CH4(g)+ 3 Cl2(g)→ 2 CHCl3(l)+ 3 H2(g)

H° = ?

Accepted Answer

A) -1420 kJ mol-1 
B) -708 kJ mol-1 
C) +708 kJ mol-1 
D) +1420 kJ mol-1 
A) -1420 kJ mol-1 
B) -708 kJ mol-1 
C) +708 kJ mol-1 
D) +1420 kJ mol-1

Question 10

Oxygen gas at 34.5 °C is compressed from 45.7 L to 34.5 L against a constant pressure of 750 mmHg.What is the work done in joules by the system?

Accepted Answer

A) 1.12 × 103 J 
B) -1.12 × 103 J 
C) 9.09 × 104 J 
D) -9.09 × 104 J 
E) 4.55 × 103 J 
A) 1.12 × 103 J 
B) -1.12 × 103 J 
C) 9.09 × 104 J 
D) -9.09 × 104 J 
E) 4.55 × 103 J

Question 11

Given that ΔfH°[CO(g)] = -110.5 kJ/mol and ΔfH° [COCl2(g)] = -219.1 kJ/mol,what is the enthalpy of reaction for the formation of phosgene,COCl2 from carbon monoxide,CO,and chlorine gas,Cl2(g)?

Accepted Answer

A) +110.5 kJ /mol 
B) -110.5 kJ/mol 
C) +329.6 kJ /mol 
D) -108.6 kJ/mol 
E) -219.1 kJ/mol 
A) +110.5 kJ /mol 
B) -110.5 kJ/mol 
C) +329.6 kJ /mol 
D) -108.6 kJ/mol 
E) -219.1 kJ/mol

Question 12

Determine △rH° for the decomposition of hydrogen peroxide.
H2O2(l)→1/2 O2(g)+ H2O(l)
Given: H2(g)+ O2(g)→ H2O2(l)△rH° = -187.78 kJ/mol
H2(g)+ 1/2 O2(g)→ H2O(l)△rH° = -285.83 kJ/mol

Accepted Answer

A) -98.05 kJ/mol 
B) +93.89 kJ/mol 
C) -191.94 kJ/mol 
D) -93.89 kJ/mol 
A) -98.05 kJ/mol 
B) +93.89 kJ/mol 
C) -191.94 kJ/mol 
D) -93.89 kJ/mol

Question 13

Given that ΔfH° [Ag2S(s)] = -32.6 kJ/mole,what is the enthalpy change for the precipitation of argentite,Ag2S(s)?
ΔfH° [Ag+(aq)] = +105.6 kJ/mol
ΔfH° [S2-(aq)] = +33.05 kJ/mol

Accepted Answer

A) -276.9 kJ/mol 
B) -106.1 kJ/mol 
C) +171.2 kJ/mol 
D) +106.1 kJ/mol 
E) +138.7 kJ/mol 
A) -276.9 kJ/mol 
B) -106.1 kJ/mol 
C) +171.2 kJ/mol 
D) +106.1 kJ/mol 
E) +138.7 kJ/mol

Question 14

The complete combustion of propane,C3H8(g),is represented by the equation:
C3H8(g)+ 5 O2(g)→ 3 CO2(g)+ 4 H2O(l)ΔrH° = -2220 kJ/mol
How much heat is evolved in the complete combustion of 2.50 g C3H8(g)?

Accepted Answer

A) 245 kJ 
B) 50.4 kJ 
C) 126 kJ 
D) 5.56 kJ 
E) 2.22 kJ 
A) 245 kJ 
B) 50.4 kJ 
C) 126 kJ 
D) 5.56 kJ 
E) 2.22 kJ

Question 15

For a process at constant pressure,49,600 calories of heat are released.This quantity of heat is equivalent to:

Accepted Answer

A) 4.82 × 10-6 J 
B) 1.19 × 104 J 
C) 1.24 × 104 J 
D) 2.08 × 105 J 
A) 4.82 × 10-6 J 
B) 1.19 × 104 J 
C) 1.24 × 104 J 
D) 2.08 × 105 J

Question 16

In the presence of excess oxygen,methane gas burns in a constant-pressure system to yield carbon dioxide and water: 
CH4(g)+2O2 (g)→ CO2(g)+ 2H2O (l) 
  H = -890.0 kJ
Calculate the value of q (kJ)in this exothermic reaction when 1.90 g of methane is combusted at constant pressure.

Accepted Answer

A) -105.7 kJ 
B) 0.0342 kJ 
C) -0.0095 kJ 
D) 29.3 kJ 
E) -1.06 × 105 kJ 
A) -105.7 kJ 
B) 0.0342 kJ 
C) -0.0095 kJ 
D) 29.3 kJ 
E) -1.06 × 105 kJ

Question 17

100.0 g of Cu (specific heat = 0.385 J/g °C)at 100.0 °C is added to 140.0 mL of H2O (specific heat = 4.184 J/g °C)at 25.0 °C.What is the final temperature of the mixture?

Accepted Answer

A) 56.3 °C 
B) 29.6 °C 
C) 62.5 °C 
D) 91.4 °C 
E) 33.7 °C 
A) 56.3 °C 
B) 29.6 °C 
C) 62.5 °C 
D) 91.4 °C 
E) 33.7 °C

Question 18

Some "beetles" defend themselves by spraying hot quinone,C6H4O2(l),at their enemies.Calculate △rH° for this reaction.
C6H4(OH)2(l)+ H2O2(l)→ C6H4O2(l)+ 2 H2O(l)
Given: C6H4(OH)2(l)→ C6H4O2(l)+ H2(g)+177.4 kJ/mol
The standard enthalpies of formation of H2O2(l)and H2O(l)are -187.4 and -285.8 kJ/mol,respectively.

Accepted Answer

A) -206.8 kJ/mol 
B) -384.2 kJ/mol 
C) -561.6 kJ/mol 
D) +79.00 kJ/mol 
A) -206.8 kJ/mol 
B) -384.2 kJ/mol 
C) -561.6 kJ/mol 
D) +79.00 kJ/mol

Question 19

What is the work in joules done on the system to compress He gas from 24.0 L to 12.5 L against a pressure of 1.5 atm at a constant temperature of 37.4 °C?

Accepted Answer

A) 5.5 × 103 J 
B) -17 J 
C) 17 J 
D) 1.7 × 103 J 
E) -1.7 × 103 J 
A) 5.5 × 103 J 
B) -17 J 
C) 17 J 
D) 1.7 × 103 J 
E) -1.7 × 103 J

Question 20

Choose the INCORRECT statement.

Accepted Answer

A) The surroundings are the part of the universe that is studied. 
B) Thermal energy is energy associated with random molecular motion. 
C) Chemical energy is associated with chemical bonds and intermolecular forces. 
D) Energy is the capacity to do work. 
E) Work is done when a force acts through a distance. 
A) The surroundings are the part of the universe that is studied. 
B) Thermal energy is energy associated with random molecular motion. 
C) Chemical energy is associated with chemical bonds and intermolecular forces. 
D) Energy is the capacity to do work. 
E) Work is done when a force acts through a distance.

Exam 7: Thermochemistry

The specific heat capacity of methane gas is 2.20 J g-1k-1.How many joules of heat are needed to raise the temperature of 5.00 g of methane from 36.0 °C to 75.0 °C?

The specific heat capacity of liquid water is 4.184 J g-1k-1.How many joules of heat are needed to raise the temperature of 6.00 g of water from 36.0 °C to 75.0 °C?

Cyclohexanol,C6H12O,has a heat of combustion of -890.7 kcal/mol.A sample containing 0.708 g of cyclohexanol undergoes complete combustion in a bomb calorimeter that has a heat capacity of 2.70 kcal/ °C.What is the final temperature if the initial water temperature is 27.0 °C?

For the reaction H2(g)+ 1/2 O2(g)→ H2O(g)ΔrH° = -241.8 kJ/mol, What quantity of heat is liberated by the reaction of 10.0 L of O2 measured at 22.0 °C and 742 mmHg?

A 5.00 g sample of liquid water at 25.0 °C is heated by the addition of 145 J of energy.The final temperature of the water is ________ °C.The specific heat capacity of liquid water is

The maximum amount of work is provided by a reversible process because equilibrium between the system and the surroundings is always maintained.

A certain reaction releases 10.1 kJ at constant volume and at constant pressure releases 8.4 kJ.What is △U for the reaction?

A system that absorbs heat is an exothermic system.

When 1.50 mol of CH4(g)reacts with excess Cl2(g)at constant pressure according to the chemical equation shown below,1062 kJ of heat are released.Calculate the value of ΔH for this reaction,as written. 2 CH4(g)+ 3 Cl2(g)→ 2 CHCl3(l)+ 3 H2(g) H° = ?

Oxygen gas at 34.5 °C is compressed from 45.7 L to 34.5 L against a constant pressure of 750 mmHg.What is the work done in joules by the system?

Given that ΔfH°[CO(g)] = -110.5 kJ/mol and ΔfH° [COCl2(g)] = -219.1 kJ/mol,what is the enthalpy of reaction for the formation of phosgene,COCl2 from carbon monoxide,CO,and chlorine gas,Cl2(g)?

Determine △rH° for the decomposition of hydrogen peroxide. H2O2(l)→1/2 O2(g)+ H2O(l) Given: H2(g)+ O2(g)→ H2O2(l)△rH° = -187.78 kJ/mol H2(g)+ 1/2 O2(g)→ H2O(l)△rH° = -285.83 kJ/mol

Given that ΔfH° [Ag2S(s)] = -32.6 kJ/mole,what is the enthalpy change for the precipitation of argentite,Ag2S(s)? ΔfH° [Ag+(aq)] = +105.6 kJ/mol ΔfH° [S2-(aq)] = +33.05 kJ/mol

The complete combustion of propane,C3H8(g),is represented by the equation: C3H8(g)+ 5 O2(g)→ 3 CO2(g)+ 4 H2O(l)ΔrH° = -2220 kJ/mol How much heat is evolved in the complete combustion of 2.50 g C3H8(g)?

For a process at constant pressure,49,600 calories of heat are released.This quantity of heat is equivalent to:

In the presence of excess oxygen,methane gas burns in a constant-pressure system to yield carbon dioxide and water: CH4(g)+2O2 (g)→ CO2(g)+ 2H2O (l) H = -890.0 kJ Calculate the value of q (kJ)in this exothermic reaction when 1.90 g of methane is combusted at constant pressure.

100.0 g of Cu (specific heat = 0.385 J/g °C)at 100.0 °C is added to 140.0 mL of H2O (specific heat = 4.184 J/g °C)at 25.0 °C.What is the final temperature of the mixture?

What is the work in joules done on the system to compress He gas from 24.0 L to 12.5 L against a pressure of 1.5 atm at a constant temperature of 37.4 °C?

Choose the INCORRECT statement.

Matter: Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

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

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The specific heat capacity of methane gas is 2.20 J g^-1k^-1.How many joules of heat are needed to raise the temperature of 5.00 g of methane from 36.0 °C to 75.0 °C?

The specific heat capacity of liquid water is 4.184 J g^-1k^-1.How many joules of heat are needed to raise the temperature of 6.00 g of water from 36.0 °C to 75.0 °C?

Cyclohexanol,C₆H₁₂O,has a heat of combustion of -890.7 kcal/mol.A sample containing 0.708 g of cyclohexanol undergoes complete combustion in a bomb calorimeter that has a heat capacity of 2.70 kcal/ °C.What is the final temperature if the initial water temperature is 27.0 °C?

For the reaction H₂(g)+ 1/2 O₂(g)→ H₂O(g)Δ_rH° = -241.8 kJ/mol, What quantity of heat is liberated by the reaction of 10.0 L of O₂ measured at 22.0 °C and 742 mmHg?

When 1.50 mol of CH₄(g)reacts with excess Cl₂(g)at constant pressure according to the chemical equation shown below,1062 kJ of heat are released.Calculate the value of ΔH for this reaction,as written. 2 CH₄(g)+ 3 Cl₂(g)→ 2 CHCl₃(l)+ 3 H₂(g) H° = ?

Given that Δ_fH°[CO(g)] = -110.5 kJ/mol and Δ_fH° [COCl₂(g)] = -219.1 kJ/mol,what is the enthalpy of reaction for the formation of phosgene,COCl₂ from carbon monoxide,CO,and chlorine gas,Cl₂(g)?

Determine △_rH° for the decomposition of hydrogen peroxide. H₂O₂(l)→1/2 O₂(g)+ H₂O(l) Given: H₂(g)+ O₂(g)→ H₂O₂(l)△_rH° = -187.78 kJ/mol H₂(g)+ 1/2 O₂(g)→ H₂O(l)△_rH° = -285.83 kJ/mol

Given that Δ_fH° [Ag₂S(s)] = -32.6 kJ/mole,what is the enthalpy change for the precipitation of argentite,Ag₂S(s)? Δ_fH° [Ag⁺(aq)] = +105.6 kJ/mol Δ_fH° [S^2-(aq)] = +33.05 kJ/mol

The complete combustion of propane,C₃H₈(g),is represented by the equation: C₃H₈(g)+ 5 O₂(g)→ 3 CO₂(g)+ 4 H₂O(l)Δ_rH° = -2220 kJ/mol How much heat is evolved in the complete combustion of 2.50 g C₃H₈(g)?

In the presence of excess oxygen,methane gas burns in a constant-pressure system to yield carbon dioxide and water: CH₄(g)+2O₂ (g)→ CO₂(g)+ 2H₂O (l) H = -890.0 kJ Calculate the value of q (kJ)in this exothermic reaction when 1.90 g of methane is combusted at constant pressure.

100.0 g of Cu (specific heat = 0.385 J/g °C)at 100.0 °C is added to 140.0 mL of H₂O (specific heat = 4.184 J/g °C)at 25.0 °C.What is the final temperature of the mixture?