Bài tập trắc nghiệm và đáp án môn hóa đại cương

Bài tập trắc nghiệm và đáp án môn hóa đại cương Bài tập trắc nghiệm và đáp án môn hóa đại cươngBài tập trắc nghiệm và đáp án môn hóa đại cương

1 As the concentration of a solute in a solution increases, the freezing point of the solution and the vapor pressure of the solution

A) increases, increases

B) increases, decreases

C) decreases, increases

D) decreases, decreases

E) decreases, is unaffected

2 Which one of the following solutes has a limiting van't Hoff factor (i) of 3 when

dissolved in water?

A) KNO3

B) CH3 OH

C) CCl 4

D) Na 2 SO4

E) sucrose

3 The ratio of the actual value of a colligative property to the value calculated, assuming the substance to be a nonelectrolyte, is referred to as

A) Henry's law

B) vapor pressure lowering

C) the van't Hoff factor

D) freezing point depression

E) osmotic pressure

4 The ideal value of i (van't Hoff factor) for(NH4 )3 PO4

A) 1

B) 2

C) 3

D) 4

E) 5

5 Calculate the vapor pressure of a solution made by dissolving 109 grams of glucose

(molar mass = 180.2 g/mol) in 920.0 ml of water at 25 °C The vapor pressure of pure water at 25 °C is 23.76 mm Hg Assume the density of the solution is 1.00 g/ml

A) 0.278 mm Hg

B) 0.605 mm Hg

C) 22.98 mm Hg

D) 23.48 mm Hg

E) 23.76 mm Hg

6 Calculate the freezing point of a solution containing 5.0 grams of KCl and 550.0 grams of water The molal-freezing-point-depression constant (K f ) for water is 86 °C/m

A) -0.45 °C

B) +0.45 °C

C) -0.23 °C

D) +0.23 °C

E) 1.23 °C

7 The osmotic pressure of a solution formed by dissolving 25.0 mg of aspirin (C9H8O4 ) in 0.250 L of water at 25 °C is atm

A) 13.6

B) 1.14 × 10−3

C) 0.0136

D) 2.45

E) 1.38

REVIEW

1 Which of the following is a statement of the first Law of thermodynamics?

A) E k =1

2mv 2

B) A negative ΔH corresponds to an exothermic process

C) ∆E=E final − E initial

D) Energy lost by the system must be gained by the surroundings

E) 1 cal = 4.184 J (exactly)

2 The internal energy can be increased by

(a) transferring heat from the surroundings to the system

(b) transferring heat from the system to the surroundings

(c) doing work on the system

A) a only

B) b only

C) c only

D) a and c

E) b and c

3 A ΔH corresponds to an process

A) negative, endothermic

B) positive, exothermic

C) positive, endothermic

D) zero, exothermic

E) zero, endothermic

4 Of the following, which one is a state function?

A) H

B) q

C) w

D) heat

E) none of the above

5 With reference to enthalpy changes, the term standard conditions means (a) P = 1 atm

(b) some common temperature, usually 298 K

(c) V = 1 L

A) a only

B) b only

C) c only

D) a and c

E) a and b

6 The value of ΔE for a system that performs 213 kJ of work on its surroundings and loses

79 kJ of heat is kJ

A) +292

B) -292

C) +134

D) -134

E) -21

7 The value of ∆ ° H for the reaction below is -126 kJ kJ are released when 2.00 mol of NaOH is formed in the reaction?

A) 252

B) 63

C) 3.9

D) 7.8

E) -126

8 The value of ∆ ° H for the reaction below is -72 kJ kJ of heat are released when 1.0 mol of HBr is formed in this reaction

A) 144

B) 72

C) 0.44

D) 36

E) -72

9 Given the data in the table below, ∆H °rxn for the reaction

A) -79.0

B) -1048.0

C) -476.4

D) -492.6

E) The value of ∆ H° f of O2 (g) is required for the calculation

10 For which one of the following reactions is the value of ∆H° rxn equal to ∆ H°f for the product?

11 ) ΔH for the reaction

is kJ, give the data below

A) +355

B) -1135

C) +1135

D) +35

E) -35

12 The specific heat of bromine liquid is 0.226 J/g · K The molar heat capacity (in J/mol-K)

of bromine liquid is

A) 707

B) 36.1

C) 18.1

D) 9.05

E) 0.226

13 The value of ∆ °S for the catalytic hydrogenation of acetylene to ethene,

is J/K∙ mol

A) +18.6

B) +550.8

C) +112.0

D) -112.0

E) -18.6

14 The combustion of acetylene in the presence of excess oxygen yields carbon dioxide and water:

The value of ∆ °S for this reaction is J/K∙ mol

A) +689.3

B) +122.3

C) +432.4

D) -122.3

E) -432.4

15 The value of ∆ G° at 25 C° for the decomposition of POCl3 into its constituent elements,

is kJ/mol

A) -1,108.7

B) +1,108.7

C) -606.2

D) +606.2

E) -1,005

16 KP = 0.0198 at 721 K for the reaction

In a particular experiment, the partial pressures of H 2 and I 2 at equilibrium are 0.710 and 0.888 atm, respectively The partial pressure of HI is atm

A) 7.87

B) 1.98

C) 5.64

D) 0.125

E) 0.389

17 At 400 K, the equilibrium constant for the reaction

is KP = 7.0 p A closed vessel at 400 K is charged with 1.00 atm of Br 2 (g), 1.00 atm of

Cl 2 (g), and 2.00 atm of BrCl(g) Use Q to determine which of the statements below is true

A) The equilibrium partial pressures of Br 2 ,Cl 2 , and BrCl will be the same as the initial values

B) The equilibrium partial pressure of Br 2 will be greater than 1.00 atm

C) At equilibrium, the total pressure in the vessel will be less than the initial total

pressure

D) The equilibrium partial pressure of BrCl(g) will be greater than 2.00 atm

E) The reaction will go to completion since there are equal amounts of Br 2 andCl 2

18 Given the following reaction at equilibrium, if Kc = 6.44 x 105 at 230.0 °C, K p =

_

A) 3.67 x 10−2

B) 1.56 x 104

C) 6.44 x 105

D) 2.66 x 106

E) 2.67 x 107

19 What is the order of the reaction with respect to ClO2 ?

A) 1

B) 0

C) 2

D) 3

E) 4

20 What is the order of the reaction with respect to OH− ?

A) 0

B) 1

C) 2

D) 3

E) 4

1 As the concentration of a solute in a solution increases, the freezing point of the solution and the vapor pressure of the solution

A) increases, increases

B) increases, decreases

C) decreases, increases

D) decreases, decreases

E) decreases, is unaffected

2 Which one of the following solutes has a limiting van't Hoff factor (i) of 3 when

dissolved in water?

A) KNO3

B) CH3 OH

C) CCl 4

D) Na 2 SO4

E) sucrose

3 The ratio of the actual value of a colligative property to the value calculated, assuming the substance to be a nonelectrolyte, is referred to as

A) Henry's law

B) vapor pressure lowering

C) the van't Hoff factor

D) freezing point depression

E) osmotic pressure

4 The ideal value of i (van't Hoff factor) for(NH4 )3 PO4

A) 1

B) 2

C) 3

D) 4

E) 5

5 Calculate the vapor pressure of a solution made by dissolving 109 grams of glucose

(molar mass = 180.2 g/mol) in 920.0 ml of water at 25 °C The vapor pressure of pure water at 25 °C is 23.76 mm Hg Assume the density of the solution is 1.00 g/ml

A) 0.278 mm Hg

B) 0.605 mm Hg

C) 22.98 mm Hg

D) 23.48 mm Hg

E) 23.76 mm Hg

6 Calculate the freezing point of a solution containing 5.0 grams of KCl and 550.0 grams of water The molal-freezing-point-depression constant (K f ) for water is 86 °C/m

A) -0.45 °C

B) +0.45 °C

C) -0.23 °C

D) +0.23 °C

E) 1.23 °C

7 The osmotic pressure of a solution formed by dissolving 25.0 mg of aspirin (C9H8O4 ) in 0.250 L of water at 25 °C is atm

A) 13.6

B) 1.14 × 10−3

C) 0.0136

D) 2.45

E) 1.38

REVIEW

1 Which of the following is a statement of the first Law of thermodynamics?

A) E k =1

2mv 2

B) A negative ΔH corresponds to an exothermic process

C) ∆E=E final − E initial

D) Energy lost by the system must be gained by the surroundings

E) 1 cal = 4.184 J (exactly)

2 The internal energy can be increased by

(a) transferring heat from the surroundings to the system

(b) transferring heat from the system to the surroundings

(c) doing work on the system

A) a only

B) b only

C) c only

D) a and c

E) b and c

3 A ΔH corresponds to an process

A) negative, endothermic

B) positive, exothermic

C) positive, endothermic

D) zero, exothermic

E) zero, endothermic

4 Of the following, which one is a state function?

A) H

B) q

C) w

D) heat

E) none of the above

5 With reference to enthalpy changes, the term standard conditions means (a) P = 1 atm

(b) some common temperature, usually 298 K

(c) V = 1 L

A) a only

B) b only

C) c only

D) a and c

E) a and b

6 The value of ΔE for a system that performs 213 kJ of work on its surroundings and loses

79 kJ of heat is kJ

A) +292

B) -292

C) +134

D) -134

E) -21

7 The value of ∆ ° H for the reaction below is -126 kJ kJ are released when 2.00 mol of NaOH is formed in the reaction?

A) 252

B) 63

C) 3.9

D) 7.8

E) -126

8 The value of ∆ ° H for the reaction below is -72 kJ kJ of heat are released when 1.0 mol of HBr is formed in this reaction

A) 144

B) 72

C) 0.44

D) 36

E) -72

9 Given the data in the table below, ∆H °rxn for the reaction

A) -79.0

B) -1048.0

C) -476.4

D) -492.6

E) The value of ∆ H° f of O2 (g) is required for the calculation

10 For which one of the following reactions is the value of ∆H° rxn equal to ∆ H°f for the product?

D

11 ) ΔH for the reaction

is kJ, give the data below

A) +355

B) -1135

C) +1135

D) +35

E) -35

12 The specific heat of bromine liquid is 0.226 J/g · K The molar heat capacity (in J/mol-K)

of bromine liquid is

A) 707

B) 36.1

C) 18.1

D) 9.05

E) 0.226

13 The value of ∆ °S for the catalytic hydrogenation of acetylene to ethene,

is J/K∙ mol

A) +18.6

B) +550.8

C) +112.0

D) -112.0

E) -18.6

14 The combustion of acetylene in the presence of excess oxygen yields carbon dioxide and water:

The value of ∆ °S for this reaction is J/K∙ mol

A) +689.3

B) +122.3

C) +432.4

D) -122.3

E) -432.4

15 The value of ∆ G° at 25 C° for the decomposition of POCl3 into its constituent elements,

is kJ/mol

A) -1,108.7

B) +1,108.7

C) -606.2

D) +606.2

E) -1,005

16 KP = 0.0198 at 721 K for the reaction

In a particular experiment, the partial pressures of H 2 and I 2 at equilibrium are 0.710 and 0.888 atm, respectively The partial pressure of HI is atm

A) 7.87

B) 1.98

C) 5.64

D) 0.125

E) 0.389

17 At 400 K, the equilibrium constant for the reaction

is KP = 7.0 p A closed vessel at 400 K is charged with 1.00 atm of Br 2 (g), 1.00 atm of

Cl 2 (g), and 2.00 atm of BrCl(g) Use Q to determine which of the statements below is true

A) The equilibrium partial pressures of Br 2 ,Cl 2 , and BrCl will be the same as the initial values

B) The equilibrium partial pressure of Br 2 will be greater than 1.00 atm

C) At equilibrium, the total pressure in the vessel will be less than the initial total

pressure

D) The equilibrium partial pressure of BrCl(g) will be greater than 2.00 atm

E) The reaction will go to completion since there are equal amounts of Br 2 andCl 2

18 Given the following reaction at equilibrium, if Kc = 6.44 x 105 at 230.0 °C, K p =

_

A) 3.67 x 10−2

B) 1.56 x 104

C) 6.44 x 105

D) 2.66 x 106

E) 2.67 x 107

19 What is the order of the reaction with respect to ClO2 ?

A) 1

B) 0

C) 2

D) 3

E) 4

20 What is the order of the reaction with respect to OH− ?

A) 0

B) 1

C) 2

D) 3

E) 4