wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

Thermodynamics AQA A Level

Total questions: 10

Worksheet time: 30mins

Name
Class
Date
1.

Which equation represents the process that occurs when the standard enthalpy of atomisation of iodine is measured?

a)

1/2 I2(s) → I(g)

b)

I2(s) → 2I(g)

c)

1/2 I2(g) → I(g)

d)

I2(g) → 2I(g)

2.

Lattice enthalpy values can be obtained from Born–Haber cycles and by calculations based on a perfect ionic model.


Which compound shows the greatest percentage difference between these two values?

a)

CsF

b)

CsI

c)

LiF

d)

LiI

3.

Which one of the following has the most covalent character?

a)

MgF2

b)

MgBr2

c)

AlF3

d)

AlBr3

4.

In which one of the following reactions is there a decrease in entropy?

a)

[Fe(H2O)6]3+(aq) + 3C2O42- (aq) → [Fe(C2O4)3]3−(aq) + 6H2O(l)

b)

[Cu(H2O)6]2+(aq) + EDTA4−(aq) → [Cu(EDTA)]2−(aq) + 6H2O(l)

c)

[CoCl4]2−(aq) + 6H2O(l) → [Co(H2O)6]2+(aq) + 4Cl (aq)

d)

Na2CO3(s) + 2H+(aq) → 2Na+(aq) + CO2(g) + H2O(l)

5.

This question relates to the equilibrium gas-phase synthesis of sulphur trioxide:

2SO2(g) + O2(g) = 2SO3(g) (the = shows double arrows)

Thermodynamic data for the components of this equilibrium are shown in the image. This equilibrium, at a temperature of 585 K and a total pressure of 540 kPa, occurs in a vessel of volume 1.80 dm3. At equilibrium, the vessel contains 0.0500 mol of SO2(g), 0.0800 mol of O2(g) and 0.0700 mol of SO3(g). The standard entropy change for this reaction is

a)

−222 J K−1 mol−1

b)

−195 J K−1 mol−1

c)

−186 J K−1 mol−1

d)

+198 J K−1 mol−1

6.

he following information concerns the equilibrium gas-phase synthesis of methanol. CO(g) + 2H2(g) = CH3OH(g)

At equilibrium, when the temperature is 68 °C, the total pressure is 1.70 MPa.

The number of moles of CO, H2 and CH3OH present are 0.160, 0.320 and 0.180, respectively.

Thermodynamic data are given. The standard entropy change for this reaction is?

a)

−220 J K−1 mol−1

b)

+220 J K−1 mol−1

c)

−89 J K−1 mol−1

d)

+89 J K−1 mol−1

7.

A reaction is exothermic and has a negative entropy change. Which statement is correct?

a)

The reaction is always feasible

b)

The reaction is feasible above a certain temperature

c)

The reaction is feasible below a certain temperature

d)

The reaction is never feasible

8.

Using the information below, answer this question.

Fe2O3(s) + 3H2(g) → 2Fe(s) + 3H2O(g)

ΔH= +96 kJ mol−1, ΔS = +138 J K−1 mol−1

The standard entropy value for steam is?

a)

+332 J K-1 mol−1

b)

+189 J K-1 mol−1

c)

+145 J K-1 mol−1

d)

+85 J K-1 mol−1

9.

Which one of the equations below represents a reaction that is feasible at all temperatures?

a)

P(s) → Q(s) + R(g) endothermic

b)

2L(g) + M(g) → 2N(g) exothermic

c)

S(g) → 2T(g) exothermic

d)

A(g) + B(g) → C(g) endothermic

10.

Refer to the following reaction

H2(g) + I2(g) = 2HI(g)

ΔH = −11 kJ mol−1, ΔS = +20 J K−1 mol−1

Which one of the following statements is correct?

a)

This is a redox reaction.

b)

The reaction is not feasible below 298 K

c)

At equilibrium, the yield of hydrogen iodide is changed by increasing the pressure.

d)

At equilibrium, the yield of hydrogen iodide increases as the temperature is increased.