wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

Unit 3_Free Energy_Thermodynamics

Total questions: 20

Worksheet time: 19mins

Name
Class
Date
1.
ΔH value in an endothermic reaction is a positive number.
a)
True
b)
False
2.
The equation that relates enthalpy, temperature and entropy is
a)
Hess's Law
b)
Second Law of Thermodynamics
c)
Gibbs Free Energy
d)
Calorimetry
3.
A catalyst works by
a)
changing the order of the reaction
b)
increasing the temperature
c)
lowering the activation energy
d)
making the activated complex
4.
 For which of these processes is the value of ΔH expected to be positive?
1.  The temperature increases when calcium chloride dissolves in water.
2.  Steam condenses to liquid water
3.  Water boils
4.  Dry ice sublimates
a)
4 only
b)
1 only
c)
3 and 4 only
d)
2 and 3 only
5.

The thermodynamic quantity that expresses the degree of disorder in a system is _

a)

entropy

b)

internal energy

c)

heat flow

d)

enthalpy

e)

bond energy

6.

A reaction that is not spontaneous at low temperature can become spontaneous at high temperature if ΔH is __________ and ΔS is __________.

a)

+, +

b)

-, -

c)

+, -

d)

-, +

e)

+, 0

7.

For a reaction to be spontaneous under standard conditions at all temperatures, the signs of ΔHΟ and ΔSΟ must be __________ and __________, respectively.

a)

+, +

b)

+, -

c)

-, +

d)

-, -

e)

+, 0

8.

Which of the following situations demonstrates high entropy?

a)

water freezing

b)

water vaporizing

c)

steam condensing to water

9.
Which energy conversion shown below takes place in a galvanic cell?
a)
electrical to chemical
b)
mechanical to chemical
c)
mechanical to electrical
d)
chemical to electrical
10.

What is reduction?

a)

It is the gain of electrons.

b)

It is the loss of electrons.

c)

It is the creation of electrons.

d)

It is the destruction of electrons.

11.

What is a galvanic (voltaic) cell?

a)

It is a cell that destroys electrons on one side and creates electrons on the other side.

b)

It is a cell that contains only one metal bar and one aqueous ion solution.

c)

It is a type of battery that drives a redox reaction when electricity is applied.

d)

It is a type of battery that generates an electrical current from redox reactions.

12.

What is an anode?

a)

It is the electrode where oxidation takes place.

b)

It is the electrode where reduction takes place.

c)

It is an aqueous solution containing an electrode.

d)

It is the salt bridge that connects half-cells.

13.

What is a cathode?

a)

It is the electrode where oxidation takes place.

b)

It is the electrode where reduction takes place.

c)

It is an aqueous solution containing an electrode.

d)

It is the salt bridge that connects half-cells.

14.

Electrons always flow from

a)

cathode to anode

b)

anode to cathode

15.

Oxidation occurs at the

a)

anode

b)

cathode

16.

What occurs to the mass of copper electrode in the following reaction?

Zn/Zn2+ // Cu2+/Cu

a)

increases

b)

decreases

c)

remains the same

17.

What reaction occurs at the anode?

Ag+/Ag = 0.80V

Ni2+/Ni = -0.25V

a)

Ag+ + e- →Ag

b)

Ag → Ag+ + e-

c)

Ni2+ + 2e- → Ni

d)

Ni → Ni2+ + 2e-

18.

Nernst equation FOR (i) Mg(s) | Mg2+(0.001M) || Al3+(0.0001 M) | Al(s)

a)

ECELL=E0CELL-0.0591/6 log[Mg2+]3/[Al3+]2

b)

ECELL=E0CELL-0.0591/6 log[Al3+]2/[Mg2+]3

c)

ECELL=E0CELL+0.0591/3 log[Mg2+]3/[Al3+]2

d)

ECELL=E0CELL-0.0591/3 log[Mg2+] /[Al3+]

19.

Nernst equation for an electrode is based on the variation of electrode potential of an electrode with

a)

Temperature

b)

Concentration of electrolyte

c)

Both a & b

d)

Density of the electrodes

20.

Which of the following would most likely lead to a spontaneous reaction.

a)

A high negative enthalpy.

b)

A low negative enthalpy.

c)

A high positive enthalpy.

d)

A low positive enthalpy.