Which of the following possesses higher entropy:
(1) Gaseous substance
(2) Liquid substance

Explanation

(i) Heat of neutralisation or enthalpy of neutralization is defined as the change in enthalpy of the system when one-gram equivalent of an acid is completely neutralised by one-gram equivalent of base or vice versa in the dilute solution.
The enthalpy of neutralization value depends on the nature of acid or base (strong or weak).
(ii) The criteria for spontaneity in terms of free energy change is:
If `triangleG` is negative `(triangleG lt 0),` the process is spontaneous.
If `triangleG` is zero `(triangleG= 0),` the process is at equilibrium.
If `triangleG` is positive `(triangleG gt 0),` the process is non-spontaneous.
(iii) Gaseous substances possess higher entropy than liquid substances.
This is because in gaseous substances, the molecules are free to move in the space available to them, so randomness is maximum and thus maximum entropy.
While in liquid substances the molecules are free to move but only within the boundary of liquid, so randomness is less compared to gases and thus less entropy than gaseous substances.