Question 1

An isothermal change is one that occurs at a constant temperature.

Accepted Answer

A) True 
 B)False

Question 2

At constant pressure and temperature,which of the following statements is true for the reaction: 
N2O5(s)$\rightarrow$2NO2(g)+ ½O2(g),$\Delta$Hr = 109.5 kJ.mol-1  at 298 K.

Accepted Answer

A) ($\Delta$H is independent of the physical states of the reactants.) 
B) ($\Delta$H = $\Delta$U) 
C) w = 0 
D) ($\Delta$H  $\Delta$U) 
A) ($\Delta$H is independent of the physical states of the reactants.) 
B) ($\Delta$H = $\Delta$U) 
C) w = 0 
D) ($\Delta$H  $\Delta$U)

Question 3

A system had 150 kJ of work done on it and its internal energy increased by 60 kJ.How much energy did the system gain or lose as heat?

Accepted Answer

A) The system lost 90 kJ of energy as heat. 
B) The system lost 210 kJ of energy as heat. 
C) The system gained 60 kJ of energy as heat. 
D) The system gained 90 kJ of energy as heat. 
E) The system gained 210 kJ of energy as heat. 
A) The system lost 90 kJ of energy as heat. 
B) The system lost 210 kJ of energy as heat. 
C) The system gained 60 kJ of energy as heat. 
D) The system gained 90 kJ of energy as heat. 
E) The system gained 210 kJ of energy as heat.

Question 4

The formation of solid calcium oxide from a gas of its ions is an exothermic process and is equal to the reverse of the lattice enthalpy.

Accepted Answer

A) True 
 B)False

Question 5

for the reaction
N2O5(s)$\rightarrow$  2NO2(g)+ ½O2(g),$\Delta$Hr = 109.5 kJ.mol-1  at 298 K
at constant temperature and pressure,$\Delta$H > $\Delta$U.

Accepted Answer

A) True 
 B)False

Question 6

What mass of propane,C3H8(g),must be burned to supply 2580 kJ of heat? The standard enthalpy of combustion of propane at 298 K is -2220 kJ.mol-1

Accepted Answer

A) 25.6 g 
B) 51.2 g 
C) 102 g 
D) 75.9 g 
E) 37.9 g 
A) 25.6 g 
B) 51.2 g 
C) 102 g 
D) 75.9 g 
E) 37.9 g

Question 7

The standard enthalpy of formation of NaCl(s)is -411 kJ/mol.In a Born-Haber cycle for the formation of NaCl(s),which enthalpy change(s)is/are endothermic?

Accepted Answer

A) the lattice enthalpy of NaCl(s) 
B) the electron affinity of chlorine 
C) the reverse of the lattice enthalpy of NaCl(s) 
D) All of the enthalpy changes are endothermic except for the standard enthalpy of formation of NaCl(s). 
A) the lattice enthalpy of NaCl(s) 
B) the electron affinity of chlorine 
C) the reverse of the lattice enthalpy of NaCl(s) 
D) All of the enthalpy changes are endothermic except for the standard enthalpy of formation of NaCl(s).

Question 8

When a gas expands into a vacuum,w = 0.

Accepted Answer

A) True 
 B)False

Question 9

Work is reported in joules; and 1 joule = ____________

Accepted Answer

1 kg.m<sup

Question 10

Which of the following is not a state function?

Accepted Answer

A) H 
B) T 
C) U 
D) S 
E) None; they are all state functions. 
A) H 
B) T 
C) U 
D) S 
E) None; they are all state functions.

Question 11

All bond enthalpies are positive.

Accepted Answer

A) True 
 B)False

Question 12

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol N2 at 298 K and 1 atm at constant volume.

Accepted Answer

A) (-2.50 kJ) 
B) +2.50 kJ 
C) +1.00 kJ 
D) (-1.50 kJ) 
E) +1.50 kJ 
A) (-2.50 kJ) 
B) +2.50 kJ 
C) +1.00 kJ 
D) (-1.50 kJ) 
E) +1.50 kJ

Question 13

A CD player and its battery together do 500 kJ of work.The battery also releases 250 kJ of energy as heat,and the CD player releases 50 kJ as heat due to friction from spinning.What is the change in internal energy of the system,with the system regarded as the battery alone? Assume that the battery does 500 kJ of work on the CD player,which then does the same amount of work on the surroundings.

Accepted Answer

A) +200 kJ 
B) (-800 kJ) 
C) (-750 kJ) 
D) (-50 kJ) 
E) (-700 kJ) 
A) +200 kJ 
B) (-800 kJ) 
C) (-750 kJ) 
D) (-50 kJ) 
E) (-700 kJ)

Question 14

A reaction known to release 2.00 kJ of heat takes place in a calorimeter containing 0.200 L of solution and the temperature rose by 4.46S1U1P1$\circ$S1S1P0C.When 100 mL of nitric acid and 100 mL of sodium hydroxide were mixed in the same calorimeter,the temperature rose 2.0S1U1P1$\circ$S1S1P0C.What is the heat output for the neutralization reaction?

Accepted Answer

A) 0.0186 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
B) 0.448 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
C) 0.816 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
D) 17.9 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
E) 0.901 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
A) 0.0186 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
B) 0.448 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
C) 0.816 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
D) 17.9 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1  
E) 0.901 kJ-1.(S1U1P1$\circ$S1S1P0
C) -1

Question 15

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol BF3 at 298 K and 1 atm at constant volume.

Accepted Answer

A) +1.00 kJ 
B) +2.50 kJ 
C) (-1.50 kJ) 
D) (-2.50 kJ) 
E) +1.50 kJ 
A) +1.00 kJ 
B) +2.50 kJ 
C) (-1.50 kJ) 
D) (-2.50 kJ) 
E) +1.50 kJ

Question 16

A closed system can exchange energy with the surroundings.

Accepted Answer

A) True 
 B)False

Question 17

Determine$\Delta$HfS1U1P1$\circ$S1S1P0(HCl(g))from the following data. H-Cl bond enthalpy = +431 kJ.mol-1 
$\Delta$HfS1U1P1$\circ$S1S1P0(H(g))= +217.9 kJ.mol-1 
$\Delta$HfS1U1P1$\circ$S1S1P0(Cl(g))= +121.4 kJ.mol-1

Accepted Answer

A) +92 kJ.mol-1  
B) (-261 kJ.mol-1 ) 
C) (-431 kJ.mol-1 ) 
D) +431 kJ.mol-1  
E) (-92 kJ.mol-1 ) 
A) +92 kJ.mol-1  
B) (-261 kJ.mol-1 ) 
C) (-431 kJ.mol-1 ) 
D) +431 kJ.mol-1  
E) (-92 kJ.mol-1 )

Question 18

If 2.00 mol of an ideal gas at 300 K and 3.00 atm expands from 6.00 L to 18.00 L and has a final pressure of 1.20 atm,isothermally and reversibly,which of the following is correct?

Accepted Answer

A) w = -5.48 kJ,q = +5.48 kJ,$\Delta$U = 0 
B) w = -3.65 kJ,q = +3.65 kJ,$\Delta$U = 0 
C) w = +3.65 kJ,q = +3.65 kJ,$\Delta$U = +7.30 kJ 
D) w = -5.48 kJ,q = -5.48 kJ,$\Delta$U = -11.0 kJ 
E) w = +5.48 kJ,q = +5.48 kJ,$\Delta$U = +11.0 kJ 
A) w = -5.48 kJ,q = +5.48 kJ,$\Delta$U = 0 
B) w = -3.65 kJ,q = +3.65 kJ,$\Delta$U = 0 
C) w = +3.65 kJ,q = +3.65 kJ,$\Delta$U = +7.30 kJ 
D) w = -5.48 kJ,q = -5.48 kJ,$\Delta$U = -11.0 kJ 
E) w = +5.48 kJ,q = +5.48 kJ,$\Delta$U = +11.0 kJ

Question 19

For gaseous hydrogen atoms at 298 K is +217.kJ.mol-1 ,the standard enthalpy of formation can be best written as:

Accepted Answer

A) 2 H(g)$\rightarrow$ H2(g) 
B) ½H2(g)$\rightarrow$ H(g) 
C) H2(g)$\rightarrow$ 2 H(g) 
D) 2 H2(g)$\rightarrow$ 4 H(g) 
E) H(g)$\rightarrow$ ½H2(g) 
A) 2 H(g)$\rightarrow$ H2(g) 
B) ½H2(g)$\rightarrow$ H(g) 
C) H2(g)$\rightarrow$ 2 H(g) 
D) 2 H2(g)$\rightarrow$ 4 H(g) 
E) H(g)$\rightarrow$ ½H2(g)

Question 20

For Br2(l),the standard enthalpy of formation is ______________________ (positive/ negative/ zero).

Accepted Answer

An isothermal change is one that occurs at a constant temperature.

At constant pressure and temperature,which of the following statements is true for the reaction: N₂O₅(s) $\rightarrow$ 2NO₂(g)+ ½O₂(g), $\Delta$ H_r = 109.5 kJ.mol^-1 at 298 K.

A system had 150 kJ of work done on it and its internal energy increased by 60 kJ.How much energy did the system gain or lose as heat?

The formation of solid calcium oxide from a gas of its ions is an exothermic process and is equal to the reverse of the lattice enthalpy.

for the reaction N₂O₅(s) $\rightarrow$ 2NO₂(g)+ ½O₂(g), $\Delta$ H_r = 109.5 kJ.mol^-1 at 298 K at constant temperature and pressure, $\Delta$ H > $\Delta$ U.

What mass of propane,C₃H₈(g),must be burned to supply 2580 kJ of heat? The standard enthalpy of combustion of propane at 298 K is -2220 kJ.mol^-1

The standard enthalpy of formation of NaCl(s)is -411 kJ/mol.In a Born-Haber cycle for the formation of NaCl(s),which enthalpy change(s)is/are endothermic?

When a gas expands into a vacuum,w = 0.

Work is reported in joules; and 1 joule = ____________

Which of the following is not a state function?

All bond enthalpies are positive.

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol N₂ at 298 K and 1 atm at constant volume.

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol BF₃ at 298 K and 1 atm at constant volume.

A closed system can exchange energy with the surroundings.

Determine $\Delta$ H_f^$\circ$(HCl(g))from the following data. H-Cl bond enthalpy = +431 kJ.mol^-1 $\Delta$ H_f^$\circ$(H(g))= +217.9 kJ.mol^-1 $\Delta$ H_f^$\circ$(Cl(g))= +121.4 kJ.mol^-1

If 2.00 mol of an ideal gas at 300 K and 3.00 atm expands from 6.00 L to 18.00 L and has a final pressure of 1.20 atm,isothermally and reversibly,which of the following is correct?

For gaseous hydrogen atoms at 298 K is +217.kJ.mol^-1,the standard enthalpy of formation can be best written as:

For Br₂(l),the standard enthalpy of formation is ______________________ (positive/ negative/ zero).

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

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Aqueous Equilibria

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Exam 8: Thermodynamics: The First Law

An isothermal change is one that occurs at a constant temperature.

At constant pressure and temperature,which of the following statements is true for the reaction: N2O5(s) →\rightarrow→ 2NO2(g)+ ½O2(g), Δ\DeltaΔ Hr = 109.5 kJ.mol-1 at 298 K.

A system had 150 kJ of work done on it and its internal energy increased by 60 kJ.How much energy did the system gain or lose as heat?

The formation of solid calcium oxide from a gas of its ions is an exothermic process and is equal to the reverse of the lattice enthalpy.

for the reaction N2O5(s) →\rightarrow→ 2NO2(g)+ ½O2(g), Δ\DeltaΔ Hr = 109.5 kJ.mol-1 at 298 K at constant temperature and pressure, Δ\DeltaΔ H > Δ\DeltaΔ U.

What mass of propane,C3H8(g),must be burned to supply 2580 kJ of heat? The standard enthalpy of combustion of propane at 298 K is -2220 kJ.mol-1

The standard enthalpy of formation of NaCl(s)is -411 kJ/mol.In a Born-Haber cycle for the formation of NaCl(s),which enthalpy change(s)is/are endothermic?

When a gas expands into a vacuum,w = 0.

Work is reported in joules; and 1 joule = ____________

Which of the following is not a state function?

All bond enthalpies are positive.

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol N2 at 298 K and 1 atm at constant volume.

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol BF3 at 298 K and 1 atm at constant volume.

A closed system can exchange energy with the surroundings.

Determine Δ\DeltaΔ Hf ∘\circ∘ (HCl(g))from the following data. H-Cl bond enthalpy = +431 kJ.mol-1 Δ\DeltaΔ Hf ∘\circ∘ (H(g))= +217.9 kJ.mol-1 Δ\DeltaΔ Hf ∘\circ∘ (Cl(g))= +121.4 kJ.mol-1

If 2.00 mol of an ideal gas at 300 K and 3.00 atm expands from 6.00 L to 18.00 L and has a final pressure of 1.20 atm,isothermally and reversibly,which of the following is correct?

For gaseous hydrogen atoms at 298 K is +217.kJ.mol-1 ,the standard enthalpy of formation can be best written as:

For Br2(l),the standard enthalpy of formation is ______________________ (positive/ negative/ zero).

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

At constant pressure and temperature,which of the following statements is true for the reaction: N₂O₅(s) $\rightarrow$ 2NO₂(g)+ ½O₂(g), $\Delta$ H_r = 109.5 kJ.mol^-1 at 298 K.

for the reaction N₂O₅(s) $\rightarrow$ 2NO₂(g)+ ½O₂(g), $\Delta$ H_r = 109.5 kJ.mol^-1 at 298 K at constant temperature and pressure, $\Delta$ H > $\Delta$ U.

What mass of propane,C₃H₈(g),must be burned to supply 2580 kJ of heat? The standard enthalpy of combustion of propane at 298 K is -2220 kJ.mol^-1

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol N₂ at 298 K and 1 atm at constant volume.

Calculate the change in internal energy when 2.50 kJ of energy is transferred as heat to 1.50 mol BF₃ at 298 K and 1 atm at constant volume.

Determine $\Delta$ H_f^$\circ$(HCl(g))from the following data. H-Cl bond enthalpy = +431 kJ.mol^-1 $\Delta$ H_f^$\circ$(H(g))= +217.9 kJ.mol^-1 $\Delta$ H_f^$\circ$(Cl(g))= +121.4 kJ.mol^-1

For gaseous hydrogen atoms at 298 K is +217.kJ.mol^-1,the standard enthalpy of formation can be best written as:

For Br₂(l),the standard enthalpy of formation is ______________________ (positive/ negative/ zero).