Which response includes all of the following processes that are accompanied by an increase in entropy?

1. I 2 (s) ? I 2 (g)

2. 2I (g) ? I 2 (g)

3. 2NH 3 (g) ? N 2 (g) + 3H 2 (g)

4. Mg 2 + (aq) + 2OH

1 and 3.

Explanation:

The entropy measures the randomness of the system, as higher is it, as higher is the entropy. The randomness is associated with the movement and the arrangement of the molecules. Thus, if the molecules are moving faster and are more disorganized, the randomness is greater.

So, the entropy (S) of the phases increases by:

S solid < S liquid < S gases.

1. The substance is going from solid to gas, thus the entropy is increasing.

2. The substance is going from a disorganized way (the molecules of I are disorganized) to an organized way (the molecules join together to form I2), thus the entropy is decreasing.

3. The molecules go from an organized way (the atom are joined together) to a disorganized way, thus the entropy increases.

4. The ions are disorganized and react to form a more organized molecule, thus the entropy decreases.