Answer: Option (a) is the correct answer.
Explanation:
Entropy means the degree of randomness present within the molecules of an object.
When a substance is present in a solid state then its molecules are held together because of strong intermolecular forces of attraction.
As a result, molecules are not able to move freely and therefore, there will be no randomness.
But when a substance changes into liquid state then its molecules mover further apart from each other due to gain in kinetic energy. Hence, randomness increases.
On the other hand, when a substance moves from liquid to gaseous state then its molecules gain more kinetic energy due to which there will be high degree of randomness.
Therefore, as the products in the given reaction are present in liquid and gaseous state. So, this means that there has been an increase in entropy.
A decrease in entropy is represented by negative sign and an increase in entropy is represented by a positive sign.
Thus, we can conclude that the sign of for the given reaction is
> 0.