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Physical Chemistry
12 All of the following statements concerning entropy are true EXCEPT
entropy is zero for elements under standard conditions.
entropy is a state function.
a positive change in entropy denotes a change toward greater disorder.
entropy values are greater than or equal to zero.
13 All of the following processes lead to an increase in entropy EXCEPT
increasing the temperature of a gas.
freezing a liquid.
evaporating a liquid.
forming mixtures from pure substances.
14 Which reaction is likely to have a negative change in entropy?
$2 NH_3(s) \rightarrow N_2(g) + 3 H_2(g)$
$CaO(s) + CO_2(g) \rightarrow CaCO_3(s)$
$NaCl(s) \rightarrow Na^+(aq) + Cl^-(aq)$
$N_2O_4(g) \rightarrow 2 NO_2(g)$
15 Calculate the standard entropy change for the following reaction, $2
Ag_2O(s) \rightarrow 4 Ag(s) + O_2(g)$ given $S^º[Ag_2O]$ = 121.3
J/K·mol, $S^º[Ag(s)]$ = 42.6 J/K·mol, and $S^º[O_2(g)]$ = 205.1 J/K·mol.
-205.1 J/K
-126.4 J/K
+126.4 J/K
+132.9 J/K
entropy is zero for elements under standard conditions.
entropy is a state function.
a positive change in entropy denotes a change toward greater disorder.
entropy values are greater than or equal to zero.
13 All of the following processes lead to an increase in entropy EXCEPT
increasing the temperature of a gas.
freezing a liquid.
evaporating a liquid.
forming mixtures from pure substances.
14 Which reaction is likely to have a negative change in entropy?
$2 NH_3(s) \rightarrow N_2(g) + 3 H_2(g)$
$CaO(s) + CO_2(g) \rightarrow CaCO_3(s)$
$NaCl(s) \rightarrow Na^+(aq) + Cl^-(aq)$
$N_2O_4(g) \rightarrow 2 NO_2(g)$
15 Calculate the standard entropy change for the following reaction, $2
Ag_2O(s) \rightarrow 4 Ag(s) + O_2(g)$ given $S^º[Ag_2O]$ = 121.3
J/K·mol, $S^º[Ag(s)]$ = 42.6 J/K·mol, and $S^º[O_2(g)]$ = 205.1 J/K·mol.
-205.1 J/K
-126.4 J/K
+126.4 J/K
+132.9 J/K
Physical Chemistry
9 Which of the following involves a decrease in entropy?
the sublimation of carbon dioxide
the dissolution of NaCl in water
the evaporation of ethanol
the freezing of liquid water into ice
10 A statement of the second law of thermodynamics is that
the entropy of the universe is continually increasing.
energy is conserved in a chemical reaction.
spontaneous reactions are always exothermic.
the enthalpy of reaction is the difference between product and reactant
enthalpies.
11 Of the following product-favoured processes, which are endothermic?
1. the combustion of methane to produce water and carbon dioxide. 2. the
expansion of an ideal gas. 3. the melting of ice at temperatures greater
than $0^ºC$.
1 only
2 only
3 only
2 and 3
the sublimation of carbon dioxide
the dissolution of NaCl in water
the evaporation of ethanol
the freezing of liquid water into ice
10 A statement of the second law of thermodynamics is that
the entropy of the universe is continually increasing.
energy is conserved in a chemical reaction.
spontaneous reactions are always exothermic.
the enthalpy of reaction is the difference between product and reactant
enthalpies.
11 Of the following product-favoured processes, which are endothermic?
1. the combustion of methane to produce water and carbon dioxide. 2. the
expansion of an ideal gas. 3. the melting of ice at temperatures greater
than $0^ºC$.
1 only
2 only
3 only
2 and 3
Physical Chemistry
5 The heat of combustion for 1 mole of carbon to carbon dioxide is -410
kJ. How many kJ of heat would be liberated from the complete combustion
of 60.0 g of carbon?
-82 kJ
-2050 kJ
-24,600 kJ
650.2 kJ
6 If the reaction $A + B \rightarrow C$ has an equilibrium constant
greater than one, which of the following statements is correct?
The reaction is product favoured.
The reaction is not spontaneous.
The forward rate of reaction is fast.
The backward rate of reaction is slow.
7 If a chemical reaction has a positive change in entropy, $\DeltaS$, then
the reaction is exothermic.
heat goes from the system into the surroundings.
the disorder of the system increases.
the Gibbs free energy is negative.
8 Thermodynamics can be used to determine all of the following EXCEPT
the direction in which a reaction is spontaneous.
the extent to which a reaction occurs.
the rate of reaction.
the temperature at which a reaction is spontaneous.
kJ. How many kJ of heat would be liberated from the complete combustion
of 60.0 g of carbon?
-82 kJ
-2050 kJ
-24,600 kJ
650.2 kJ
6 If the reaction $A + B \rightarrow C$ has an equilibrium constant
greater than one, which of the following statements is correct?
The reaction is product favoured.
The reaction is not spontaneous.
The forward rate of reaction is fast.
The backward rate of reaction is slow.
7 If a chemical reaction has a positive change in entropy, $\DeltaS$, then
the reaction is exothermic.
heat goes from the system into the surroundings.
the disorder of the system increases.
the Gibbs free energy is negative.
8 Thermodynamics can be used to determine all of the following EXCEPT
the direction in which a reaction is spontaneous.
the extent to which a reaction occurs.
the rate of reaction.
the temperature at which a reaction is spontaneous.
Physical Chemistry
1 The temperature remains constant as energy is added to a substance.
How may the substance be changing?
From a gas to a solid
From a liquid to a solid
From a liquid to a gas
Change in the amoung of kinetic energy
2 Which process is exothermic?
the boiling of liquid nitrogen
the freezing of water
the sublimation of dry ice
the vaporization of water
3 What does it mean if the ΔH value for a chemical reaction is positive?
kinetic energy is increasing in the system
Potential energy is decreasing in the system
products have less potential energy than reactants
reactants have less potential energy than products.
4 Use the equations to answer the question. $2A + B \rightarrow A_2B$
$\DeltaH$ = –217.3 kJ; $B + C \rightarrow BC$ $\DeltaH$ = –867.5 kJ.
What is the value of $\DeltaH$ for the reaction $2A + BC \rightarrow
A_2B + C$?
1084.8 kJ
650.2 kJ
–650.2 kJ
–1084.8 kJ
How may the substance be changing?
From a gas to a solid
From a liquid to a solid
From a liquid to a gas
Change in the amoung of kinetic energy
2 Which process is exothermic?
the boiling of liquid nitrogen
the freezing of water
the sublimation of dry ice
the vaporization of water
3 What does it mean if the ΔH value for a chemical reaction is positive?
kinetic energy is increasing in the system
Potential energy is decreasing in the system
products have less potential energy than reactants
reactants have less potential energy than products.
4 Use the equations to answer the question. $2A + B \rightarrow A_2B$
$\DeltaH$ = –217.3 kJ; $B + C \rightarrow BC$ $\DeltaH$ = –867.5 kJ.
What is the value of $\DeltaH$ for the reaction $2A + BC \rightarrow
A_2B + C$?
1084.8 kJ
650.2 kJ
–650.2 kJ
–1084.8 kJ
Physical Chemistry
Which of the following is not a state function?
enthalpy
entropy
work
free energy
enthalpy
entropy
work
free energy
Physical Chemistry
19 Calculate the $\Delta H$ value of the reaction: $$HCl + NH_3
\rightarrow NH_4Cl$$ $\Delta H^o$ values for HCl, $NH_{3}$ and
$NH_{4}Cl$ are -92.30, -80.29 and -314.4 respectively
141.8
252.88
-486.99
-141.8
20 The specific heat of silver is 0.0565 $cal/g/^{o}C$. Assuming no loss
of heat to the surroundings or to the container, calculate the final
temperature when 100 g of silver at 40 $^{o}C$ is immersed in 60 g of
water at 10 $^{o}C$.
12.6 $^o C$
25 $^oC$
16.2 $^oC$
21.6 $^oC$.
\rightarrow NH_4Cl$$ $\Delta H^o$ values for HCl, $NH_{3}$ and
$NH_{4}Cl$ are -92.30, -80.29 and -314.4 respectively
141.8
252.88
-486.99
-141.8
20 The specific heat of silver is 0.0565 $cal/g/^{o}C$. Assuming no loss
of heat to the surroundings or to the container, calculate the final
temperature when 100 g of silver at 40 $^{o}C$ is immersed in 60 g of
water at 10 $^{o}C$.
12.6 $^o C$
25 $^oC$
16.2 $^oC$
21.6 $^oC$.
Physical Chemistry
16 One mole of an ideal gas is heated at a constant pressure of 101300 N
$m^{2}$, from 273.2 K to 373 K. Calculate the work involved R = 8.314
J/mol/K).
8.314 J/mol
83.14 J/mol
831.4 J/mol
8314 J/mol
17 Which of these followings would lead to an increase in the internal
energy of a system?
Work done on the system
Work done by the system
Loss of heat from the system
Adiabatic expansion of the system
18 Which of the following statements about enthalpy is incorrect?
Enthalpy and internal energy of a system are always identical
enthalpy is a state function
$\Delta H$ is the enthalpy change at constant pressure
Reactions which absorb heat have a positive DH
$m^{2}$, from 273.2 K to 373 K. Calculate the work involved R = 8.314
J/mol/K).
8.314 J/mol
83.14 J/mol
831.4 J/mol
8314 J/mol
17 Which of these followings would lead to an increase in the internal
energy of a system?
Work done on the system
Work done by the system
Loss of heat from the system
Adiabatic expansion of the system
18 Which of the following statements about enthalpy is incorrect?
Enthalpy and internal energy of a system are always identical
enthalpy is a state function
$\Delta H$ is the enthalpy change at constant pressure
Reactions which absorb heat have a positive DH
Physical Chemistry
11 Which of these is true of an isochoric system?
Takes place at constant temperature
Heat is allowed into the system but not allowed out of the system
Volume remains constant
Pressure is not constant
12 The molar heat capacity of Al is 24.4 J/mol/$^{o}C$. How much heat
energy is required to heat 100 g of Al from 20 $^{o}C$ to 80 $^{o}C$?
(Al = 27)
146000 J
30000 J
813000 J
5422 J
13 The first law of thermodynamics deals with
conservation of energy
thermodynamic equivalence
entropy
absolute zero temperature.
14 Which of the following expressions is associated with the law of
conservation of energy?
dG = dH – TdS
q = mCdT
dE = q + w
H = E + PV
15 If a gas absorbs 1000 J of heat and expands by 0.5 $dm^{3}$ against a
constant pressure of 4 atms (1 atm = 100000 Pa), then the change in
internal energy is approximately
-800 J
800 J
1200 J
-1200 J
Takes place at constant temperature
Heat is allowed into the system but not allowed out of the system
Volume remains constant
Pressure is not constant
12 The molar heat capacity of Al is 24.4 J/mol/$^{o}C$. How much heat
energy is required to heat 100 g of Al from 20 $^{o}C$ to 80 $^{o}C$?
(Al = 27)
146000 J
30000 J
813000 J
5422 J
13 The first law of thermodynamics deals with
conservation of energy
thermodynamic equivalence
entropy
absolute zero temperature.
14 Which of the following expressions is associated with the law of
conservation of energy?
dG = dH – TdS
q = mCdT
dE = q + w
H = E + PV
15 If a gas absorbs 1000 J of heat and expands by 0.5 $dm^{3}$ against a
constant pressure of 4 atms (1 atm = 100000 Pa), then the change in
internal energy is approximately
-800 J
800 J
1200 J
-1200 J
Physical Chemistry
6 1. 43.4 kcal of heat is required to decompose 2 mole of mercury(II)
oxide according to the equation $$2HgO(s) \rightarrow 2Hg(l) + O_2
(g)$$. What quantity of energy is required to decompose 10.8 g of HgO?
(Hg = 200.59, O = 16)
2.17 kcal
1.09 kcal
468.72 kJ
0.545 kJ
7 Which of the following is not a state function?
enthalpy
entropy
work
free energy
8 The zeroth law of thermodynamics is based on the concept of
entropy
Conservation of energy
absolute zero temperature
thermodynamic equivalence
9 A process in which no heat is allowed to enter or leave a system is
termed –
Isothermal
Adiabatic
isobaric
Isochoric
10 A process taking place at constant pressure is termed –
Isothermal
Adiabatic
Isobaric
Isochoric
oxide according to the equation $$2HgO(s) \rightarrow 2Hg(l) + O_2
(g)$$. What quantity of energy is required to decompose 10.8 g of HgO?
(Hg = 200.59, O = 16)
2.17 kcal
1.09 kcal
468.72 kJ
0.545 kJ
7 Which of the following is not a state function?
enthalpy
entropy
work
free energy
8 The zeroth law of thermodynamics is based on the concept of
entropy
Conservation of energy
absolute zero temperature
thermodynamic equivalence
9 A process in which no heat is allowed to enter or leave a system is
termed –
Isothermal
Adiabatic
isobaric
Isochoric
10 A process taking place at constant pressure is termed –
Isothermal
Adiabatic
Isobaric
Isochoric
Physical Chemistry
1 Which of these does not depict thermodynamics?
Performance of car engine
Rate of reaction
Melting of ice
Boiling water for coffee
2 Which of the followings is not a type of system?
Closed
Open
Intensive
Isolated
3 Which of the following statements describes an isolated system?
No exchange of matter and energy with the surrounding is possible
only exchange of matter with the surrounding is possible
only exchange of energy with the surrounding is possible
exchange of both matter and energy with the surrounding is possible
4 Which of the following statements is correct?
Temperature is an extensive property while heat is an intensive property
temperature is an intensive property while heat is an extensive property
both temperature and heat are intensive properties
both temperature and heat are extensive properties.
5 Which of these is not an extensive property of a system?
Density
Mass
Volume
Energy
Performance of car engine
Rate of reaction
Melting of ice
Boiling water for coffee
2 Which of the followings is not a type of system?
Closed
Open
Intensive
Isolated
3 Which of the following statements describes an isolated system?
No exchange of matter and energy with the surrounding is possible
only exchange of matter with the surrounding is possible
only exchange of energy with the surrounding is possible
exchange of both matter and energy with the surrounding is possible
4 Which of the following statements is correct?
Temperature is an extensive property while heat is an intensive property
temperature is an intensive property while heat is an extensive property
both temperature and heat are intensive properties
both temperature and heat are extensive properties.
5 Which of these is not an extensive property of a system?
Density
Mass
Volume
Energy
