Question 1

Combustion reactions can be exothermic or endothermic.

Accepted Answer

A) True 
 B)False

Question 2

A piece of a newly synthesized material of mass 12.0 g at 88.0S1U1P1$\circ$S1S1P0C is placed in a calorimeter containing 100.0 g of water at 20.0S1U1P1$\circ$S1S1P0C.If the final temperature of the system is 24.0S1U1P1$\circ$S1S1P0C,what is the specific heat capacity of this material?

Accepted Answer

A) 10.2 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
B) 1.58 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
C) 2.18 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
D) 9.50 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
E) 0.54 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
A) 10.2 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
B) 1.58 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
C) 2.18 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
D) 9.50 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1  
E) 0.54 J.g-1.(S1U1P1$\circ$S1S1P0
C) -1

Question 3

The combustion of 1 mole of octane,C8H18(l),to produce carbon dioxide and liquid water has $\Delta$Hr = -5471 kJ.mol-1  at 298 K.What is the change in internal energy for this reaction?

Accepted Answer

A) (-5460 kJ.mol-1 ) 
B) (-5482 kJ.mol-1 ) 
C) (-5449 kJ.mol-1 ) 
D) (-5471 kJ.mol-1 ) 
E) (-5493 kJ.mol-1 ) 
A) (-5460 kJ.mol-1 ) 
B) (-5482 kJ.mol-1 ) 
C) (-5449 kJ.mol-1 ) 
D) (-5471 kJ.mol-1 ) 
E) (-5493 kJ.mol-1 )

Question 4

The molar heat capacity of a monatomic ideal gas is independent of temperature and pressure.

Accepted Answer

A) True 
 B)False

Question 5

If the standard enthalpy of combustion of octane,C8H18(l),at 298 K is -5471 kJ.mol-1 ,calculate the standard enthalpy of formation of octane.The standard enthalpies of formation of carbon dioxide and liquid water are -393.51 and -285.83 kJ.mol-1 ,respectively.

Accepted Answer

-249 kJ.mo

Question 6

Calculate the Br-Br bond enthalpy given the standard enthalpies of formation for Br2(g)and Br(g),30.7 and 112 kJ.mol-1 ,respectively.

Accepted Answer

A) 193 kJ.mol-1  
B) 255 kJ.mol-1  
C) 143 kJ.mol-1  
D) 81 kJ.mol-1  
E) 30.7 kJ.mol-1  
A) 193 kJ.mol-1  
B) 255 kJ.mol-1  
C) 143 kJ.mol-1  
D) 81 kJ.mol-1  
E) 30.7 kJ.mol-1

Question 7

Calculate the enthalpy change that occurs when 1.00 kg of acetone condenses at its boiling point (329.4 K).The standard enthalpy of vaporization of acetone is 29.1 kJ.mol-1.

Accepted Answer

A) (-502 kJ) 
B) (-29.1 kJ) 
C) (-2.91 * 104 kJ) 
D) +502 kJ 
E) +29.1 kJ 
A) (-502 kJ) 
B) (-29.1 kJ) 
C) (-2.91 * 104 kJ) 
D) +502 kJ 
E) +29.1 kJ

Question 8

Calculate the lattice enthalpy of potassium fluoride from the following data. enthalpy of formation of K(g): +89 kJ.mol-1 
First ionization energy of K(g): +418 kJ.mol-1 
Enthalpy of formation of F(g): +79 kJ.mol-1 
Electron affinity of F(g): +328 ($\Delta$H = -328)kJ.mol-1 
Enthalpy of formation of KF(s): -567 kJ.mol-1

Accepted Answer

A) 1481 kJ.mol-1  
B) 825 kJ.mol-1  
C) 904 kJ.mol-1  
D) 497 kJ.mol-1  
E) 347 kJ.mol-1  
A) 1481 kJ.mol-1  
B) 825 kJ.mol-1  
C) 904 kJ.mol-1  
D) 497 kJ.mol-1  
E) 347 kJ.mol-1

Question 9

What equation corresponds to the standard enthalpy of formation of gaseous hydrogen atoms,which,at 298 K is +217 kJ.mol-1 ?

Accepted Answer

½H<sub>2</

Question 10

A reaction known to release 4.00 kJ of heat takes place in a calorimeter containing 0.200 L of solution and the temperature rose by 6.14S1U1P1$\circ$S1S1P0C.When 200 mL of hydrochloric acid was added to a small piece of calcium carbonate in the same calorimeter,the temperature rose by 4.25S1U1P1$\circ$S1S1P0C.What is the heat output for this reaction?

Accepted Answer

A) 0.0257 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
B) 0.941 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
C) 0.651 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
D) 2.77 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
E) 2.12 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
A) 0.0257 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
B) 0.941 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
C) 0.651 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
D) 2.77 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
E) 2.12 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1

Question 11

When nitrogen gas expands from 3.00 to 6.00 L and 2.00 kJ of energy is transferred as heat to the nitrogen in a cylinder fitted with a piston at an external pressure of 2.00 atm,against this constant pressure,what is $\Delta$U for the process?

Accepted Answer

A) (-0.608 kJ) 
B) +2.61 kJ 
C) (-2.61 kJ) 
D) 0 
E) +1.39 kJ 
A) (-0.608 kJ) 
B) +2.61 kJ 
C) (-2.61 kJ) 
D) 0 
E) +1.39 kJ

Question 12

Calculate the enthalpy change that occurs when 1 lb (454 G)of mercury freezes at its freezing point (234.3 K).The standard enthalpy of fusion of mercury is 2.29 kJ.mol-1.

Accepted Answer

A) (-2.29 kJ ) 
B) (-1.04 * 103 kJ) 
C) +5.18 kJ 
D) +2.29 kJ 
E)  -5.18 kJ 
A) (-2.29 kJ ) 
B) (-1.04 * 103 kJ) 
C) +5.18 kJ 
D) +2.29 kJ 
E)  -5.18 kJ

Question 13

Calculate the standard reaction enthalpy for the reaction. 
N2H4(l)+ H2(g)$\rightarrow$2NH3(g)
Given:
N2H4(l)+ O2(g)$\rightarrow$N2(g)+ 2H2O(g)
$\Delta$H° = -543 kJ.mol-1 
2H2(g)+ O2(g)$\rightarrow$2H2O(g)
$\Delta$H° = -484 kJ.mol-1 
N2(g)+ 3H2(g)$\rightarrow$ 2NH3(g)
$\Delta$H° = -92.2 kJ.mol-1

Accepted Answer

A) (-935 kJ.mol-1 ) 
B) (-1119 kJ.mol-1 ) 
C) (-151 kJ.mol-1 ) 
D) (-59 kJ.mol-1 ) 
E) (-243 kJ.mol-1 ) 
A) (-935 kJ.mol-1 ) 
B) (-1119 kJ.mol-1 ) 
C) (-151 kJ.mol-1 ) 
D) (-59 kJ.mol-1 ) 
E) (-243 kJ.mol-1 )

Question 14

Calculate the lattice enthalpy of silver chloride from the following data. enthalpy of formation of Ag(g): +284 kJ.mol-1 
First ionization energy of Ag(g): +731 kJ.mol-1 
Enthalpy of formation of Cl(g): +122 kJ.mol-1 
Electron affinity of Cl(g): +349 ($\Delta$H = kJ.mol-1  )
Enthalpy of formation of AgCl(s): -127 kJ.mol-1

Accepted Answer

A) 1613 kJ.mol-1  
B) 915 kJ.mol-1  
C) 1037 kJ.mol-1  
D) 1359 kJ.mol-1  
E) 661 kJ.mol-1  
A) 1613 kJ.mol-1  
B) 915 kJ.mol-1  
C) 1037 kJ.mol-1  
D) 1359 kJ.mol-1  
E) 661 kJ.mol-1

Question 15

Calculate the lattice enthalpy of calcium oxide from the following data. enthalpy of formation of Ca(g): +178 kJ.mol-1 
First ionization energy of Ca(g): +590 kJ.mol-1 
Second ionization energy of Ca(g): +1150 kJ.mol-1 
Enthalpy of formation of O(g): +249 kJ.mol-1 
First electron affinity of O(g): +141 ($\Delta$H = -141)kJ.mol-1 
Second electron affinity of O(g): -844 ($\Delta$H = +844)kJ.mol-1 
Enthalpy of formation of CaO(s): -635 kJ.mol-1

Accepted Answer

A) 1817 kJ.mol-1  
B) 1391 kJ.mol-1  
C) 2235 kJ.mol-1  
D) 3754 kJ.mol-1  
E) 3505 kJ.mol-1  
A) 1817 kJ.mol-1  
B) 1391 kJ.mol-1  
C) 2235 kJ.mol-1  
D) 3754 kJ.mol-1  
E) 3505 kJ.mol-1

Question 16

Use the following information to determine the standard enthalpy of formation of NH3(g). N-H bond enthalpy = 390 kJ.mol-1 
$\Delta$HfS1U1P1$\circ$S1S1P0(H(g))= 217.9 kJ.mol-1 
$\Delta$HfS1U1P1$\circ$S1S1P0(N(g))= 472.6 kJ.mol-1

Accepted Answer

A) (-44 kJ.mol-1 ) 
B) (-691 kJ.mol-1 ) 
C) (-516 kJ.mol-1 ) 
D) (-83 kJ.mol-1 ) 
E) (-1170 kJ.mol-1 ) 
A) (-44 kJ.mol-1 ) 
B) (-691 kJ.mol-1 ) 
C) (-516 kJ.mol-1 ) 
D) (-83 kJ.mol-1 ) 
E) (-1170 kJ.mol-1 )

Question 17

Calculate the standard reaction enthalpy for the following reaction. 
CH4(g)+ H2O(g)$\rightarrow$ CO(g)+ 3H2(g)
Given:
2H2(g)+ CO(g)$\rightarrow$CH3OH(l)
$\Delta$H° = -128.3 kJ.mol-1 
2CH4(g)+ O2(g)$\rightarrow$2CH3OH(l)
$\Delta$H° = -328.1 kJ.mol-1 
2H2(g)+ O2(g)$\rightarrow$2H2O(g)
$\Delta$H° = -483.6 kJ.mol-1

Accepted Answer

A) +155.5 kJ.mol-1  
B) + 216 kJ.mol-1  
C) +412.1 kJ.mol-1  
D) +42.0 kJ.mol-1  
E) +206.1 kJ.mol-1  
A) +155.5 kJ.mol-1  
B) + 216 kJ.mol-1  
C) +412.1 kJ.mol-1  
D) +42.0 kJ.mol-1  
E) +206.1 kJ.mol-1

Question 18

What mass of ethanol,C2H5OH(l),must be burned to supply 500 kJ of heat? The standard enthalpy of combustion of ethanol at 298 K is -1368 kJ.mol-1

Accepted Answer

A) 126 g 
B) 2.74 g 
C) 16.8 g 
D) 10.9 g 
E) 29.7 g 
A) 126 g 
B) 2.74 g 
C) 16.8 g 
D) 10.9 g 
E) 29.7 g

Question 19

How much heat is required to vaporize 50.0 g of water if the initial temperature of the water is 25.0S1U1P1$\circ$S1S1P0C and the water is heated to its boiling point,where it is converted to steam? The specific heat capacity of water is 4.18 J.(S1U1P1$\circ$S1S1P0C)-1.g-1 and the standard enthalpy of vaporization of water at its boiling point is 40.7 kJ.mol-1.

Accepted Answer

A) 169 kJ 
B) 64.2 kJ 
C) 40.7 kJ 
D) 193 kJ 
E) 23.5 kJ 
A) 169 kJ 
B) 64.2 kJ 
C) 40.7 kJ 
D) 193 kJ 
E) 23.5 kJ

Question 20

How much work is done by a person of mass 185 kg who climbs a ladder to the top of his house,a total of 15.0 m?

Accepted Answer

A) 2.78 kJ 
B) 12.3 kJ 
C) 27.2 kJ 
D) No work is done. 
E) 121 kJ 
A) 2.78 kJ 
B) 12.3 kJ 
C) 27.2 kJ 
D) No work is done. 
E) 121 kJ

Combustion reactions can be exothermic or endothermic.

A piece of a newly synthesized material of mass 12.0 g at 88.0^$\circ$C is placed in a calorimeter containing 100.0 g of water at 20.0^$\circ$C.If the final temperature of the system is 24.0^$\circ$C,what is the specific heat capacity of this material?

The combustion of 1 mole of octane,C₈H₁₈(l),to produce carbon dioxide and liquid water has $\Delta$ H_r = -5471 kJ.mol^-1 at 298 K.What is the change in internal energy for this reaction?

The molar heat capacity of a monatomic ideal gas is independent of temperature and pressure.

If the standard enthalpy of combustion of octane,C₈H₁₈(l),at 298 K is -5471 kJ.mol^-1,calculate the standard enthalpy of formation of octane.The standard enthalpies of formation of carbon dioxide and liquid water are -393.51 and -285.83 kJ.mol^-1,respectively.

Calculate the Br-Br bond enthalpy given the standard enthalpies of formation for Br₂(g)and Br(g),30.7 and 112 kJ.mol^-1,respectively.

Calculate the enthalpy change that occurs when 1.00 kg of acetone condenses at its boiling point (329.4 K).The standard enthalpy of vaporization of acetone is 29.1 kJ.mol^-1.

What equation corresponds to the standard enthalpy of formation of gaseous hydrogen atoms,which,at 298 K is +217 kJ.mol^-1?

When nitrogen gas expands from 3.00 to 6.00 L and 2.00 kJ of energy is transferred as heat to the nitrogen in a cylinder fitted with a piston at an external pressure of 2.00 atm,against this constant pressure,what is $\Delta$ U for the process?

Calculate the enthalpy change that occurs when 1 lb (454 G)of mercury freezes at its freezing point (234.3 K).The standard enthalpy of fusion of mercury is 2.29 kJ.mol^-1.

Use the following information to determine the standard enthalpy of formation of NH₃(g). N-H bond enthalpy = 390 kJ.mol^-1 $\Delta$ H_f^$\circ$(H(g))= 217.9 kJ.mol^-1 $\Delta$ H_f^$\circ$(N(g))= 472.6 kJ.mol^-1

What mass of ethanol,C₂H₅OH(l),must be burned to supply 500 kJ of heat? The standard enthalpy of combustion of ethanol at 298 K is -1368 kJ.mol^-1

How much work is done by a person of mass 185 kg who climbs a ladder to the top of his house,a total of 15.0 m?

The Quantum World

Quantum Mechanics in Action: Atoms

Chemical Bonds

Molecular Shape and Structure

The Properties of Gases

Liquids and Solids

Inorganic Materials

Thermodynamics: The Second and Third Laws

Physical Equilibria

Chemical Equilibria

Acids and Bases

Aqueous Equilibria

Electrochemistry

Chemical Kinetics

The Elements: the Main Group Elements

The Elements: The D Block

Nuclear Chemistry

Organic Chemistry I

Organic Chemistry II

Filters

Exam 8: Thermodynamics: The First Law

Combustion reactions can be exothermic or endothermic.

A piece of a newly synthesized material of mass 12.0 g at 88.0 ∘\circ∘ C is placed in a calorimeter containing 100.0 g of water at 20.0 ∘\circ∘ C.If the final temperature of the system is 24.0 ∘\circ∘ C,what is the specific heat capacity of this material?

The combustion of 1 mole of octane,C8H18(l),to produce carbon dioxide and liquid water has Δ\DeltaΔ Hr = -5471 kJ.mol-1 at 298 K.What is the change in internal energy for this reaction?

The molar heat capacity of a monatomic ideal gas is independent of temperature and pressure.

If the standard enthalpy of combustion of octane,C8H18(l),at 298 K is -5471 kJ.mol-1 ,calculate the standard enthalpy of formation of octane.The standard enthalpies of formation of carbon dioxide and liquid water are -393.51 and -285.83 kJ.mol-1 ,respectively.

Calculate the Br-Br bond enthalpy given the standard enthalpies of formation for Br2(g)and Br(g),30.7 and 112 kJ.mol-1 ,respectively.

Calculate the enthalpy change that occurs when 1.00 kg of acetone condenses at its boiling point (329.4 K).The standard enthalpy of vaporization of acetone is 29.1 kJ.mol-1.

What equation corresponds to the standard enthalpy of formation of gaseous hydrogen atoms,which,at 298 K is +217 kJ.mol-1 ?

When nitrogen gas expands from 3.00 to 6.00 L and 2.00 kJ of energy is transferred as heat to the nitrogen in a cylinder fitted with a piston at an external pressure of 2.00 atm,against this constant pressure,what is Δ\DeltaΔ U for the process?

Calculate the enthalpy change that occurs when 1 lb (454 G)of mercury freezes at its freezing point (234.3 K).The standard enthalpy of fusion of mercury is 2.29 kJ.mol-1.

Use the following information to determine the standard enthalpy of formation of NH3(g). N-H bond enthalpy = 390 kJ.mol-1 Δ\DeltaΔ Hf ∘\circ∘ (H(g))= 217.9 kJ.mol-1 Δ\DeltaΔ Hf ∘\circ∘ (N(g))= 472.6 kJ.mol-1

What mass of ethanol,C2H5OH(l),must be burned to supply 500 kJ of heat? The standard enthalpy of combustion of ethanol at 298 K is -1368 kJ.mol-1

How much work is done by a person of mass 185 kg who climbs a ladder to the top of his house,a total of 15.0 m?

The Quantum World

Quantum Mechanics in Action: Atoms

Chemical Bonds

Molecular Shape and Structure

The Properties of Gases

Liquids and Solids

Inorganic Materials

Thermodynamics: The Second and Third Laws

Physical Equilibria

Chemical Equilibria

Acids and Bases

Aqueous Equilibria

Electrochemistry

Chemical Kinetics

The Elements: the Main Group Elements

The Elements: The D Block

Nuclear Chemistry

Organic Chemistry I

Organic Chemistry II

Filters

A piece of a newly synthesized material of mass 12.0 g at 88.0^$\circ$C is placed in a calorimeter containing 100.0 g of water at 20.0^$\circ$C.If the final temperature of the system is 24.0^$\circ$C,what is the specific heat capacity of this material?

The combustion of 1 mole of octane,C₈H₁₈(l),to produce carbon dioxide and liquid water has $\Delta$ H_r = -5471 kJ.mol^-1 at 298 K.What is the change in internal energy for this reaction?

If the standard enthalpy of combustion of octane,C₈H₁₈(l),at 298 K is -5471 kJ.mol^-1,calculate the standard enthalpy of formation of octane.The standard enthalpies of formation of carbon dioxide and liquid water are -393.51 and -285.83 kJ.mol^-1,respectively.

Calculate the Br-Br bond enthalpy given the standard enthalpies of formation for Br₂(g)and Br(g),30.7 and 112 kJ.mol^-1,respectively.

Calculate the enthalpy change that occurs when 1.00 kg of acetone condenses at its boiling point (329.4 K).The standard enthalpy of vaporization of acetone is 29.1 kJ.mol^-1.

What equation corresponds to the standard enthalpy of formation of gaseous hydrogen atoms,which,at 298 K is +217 kJ.mol^-1?

When nitrogen gas expands from 3.00 to 6.00 L and 2.00 kJ of energy is transferred as heat to the nitrogen in a cylinder fitted with a piston at an external pressure of 2.00 atm,against this constant pressure,what is $\Delta$ U for the process?

Calculate the enthalpy change that occurs when 1 lb (454 G)of mercury freezes at its freezing point (234.3 K).The standard enthalpy of fusion of mercury is 2.29 kJ.mol^-1.

Use the following information to determine the standard enthalpy of formation of NH₃(g). N-H bond enthalpy = 390 kJ.mol^-1 $\Delta$ H_f^$\circ$(H(g))= 217.9 kJ.mol^-1 $\Delta$ H_f^$\circ$(N(g))= 472.6 kJ.mol^-1

What mass of ethanol,C₂H₅OH(l),must be burned to supply 500 kJ of heat? The standard enthalpy of combustion of ethanol at 298 K is -1368 kJ.mol^-1