Question

For a single substance at atmospheric pressure, classify the following as describing a spontaneous process, a nonspontaneous process, or an equilibrium system.

Drag the appropriate items to their respective bins.

Bins: Spontaneous Process, Nonspontaneous process, and Equilibrium System

1) solid melting below its melting point

2) liquid vaporizing below its boiling point

3) gas condensing below its condensation point

4) solid and liquid together at the melting point with no net freezing or melting

5) liquid vaporizing above its boiling point

6) gas condensing above its condensation point

7) liquid freezing above its freezing point

8) solid melting above its melting point

9) liquid freezing below its freezing point

10) liquid and gas together at the boiling point with no net condensation or vaporization

Answer 1

Concepts and reason

This problem is based on the concept of equilibrium system.

Gibbs free energy can be used to find whether the reaction is spontaneous, non-spontaneous or in equilibrium. If it is positive, the reaction is non-spontaneous. If Gibbs free energy is negative the system is spontaneous and if it is zero, the system is said to be in equilibrium.

Fundamentals

When a reaction proceeds in forward direction without any force applied from any external source, it is said to be spontaneous process and the process in which energy is absorbed and positive change in free energy is observed is said to be non-spontaneous process.

For a system to be in equilibrium the rate of forward and backward reaction should be equal.

(1)

Solid melting below its melting point is non-spontaneous process.

(2)

Liquid vaporizing below its boiling point is non-spontaneous process.

(3)

Gas condensing below its condensation point is spontaneous process.

(4)

Solid and liquid together at the melting point with no net freezing or melting is an equilibrium process.

(5)

Liquid vaporizing above its boiling point is spontaneous process.

(6)

Gas condensing above its condensation point is non-spontaneous process.

(7)

Liquid freezing above its freezing point is non-spontaneous process.

(8)

Solid melting above its melting point is spontaneous process.

(9)

Liquid freezing below its freezing point is spontaneous process.

(10)

Liquid and gas together at the boiling point with no net condensation or vaporization is equilibrium process.

Ans: Part 1

Solid melting below its melting point is non-spontaneous process.