Question

Maximum entropy will be in which of the following?
A. Ice
B. Liquid water
C. Snow
D. Water vapours

Answer 1

Hint: The second law of thermodynamics is that the "entropy of the universe increases for an irreversible process."
It stays consistent for a reversible process.

Complete step-by-step answer:
Entropy, signified by "S" is defined as the degree of disorders in a thermodynamic system.
It is simply the irregularity or lack of ordered structure in a thermodynamic system.
A. Ice
This is the solid form of water.
In solids, the constituent particles are tightly packed and thus are restricted to move inside the system.
Due to this the degree of disorders is very less.
Hence, it has the least entropy.
B. Liquid water
This is in the liquid state.
In liquids, the constituent particles are not tightly packed like solids and thus are not restricted to move inside the system.
The constituent particles are free to move.
Due to this the degree of disorders is more as compared to ice.
Hence, it has more entropy than ice.
C. Snow
It is a combination of ice crystals. It is in a solid state.
In solids, the constituent particles are tightly packed and thus are restricted to move inside the system. Due to this in snow, the degree of disorders is very less.
Hence, it has the least entropy.
D. Water vapours
This is the gaseous form of water.
In gases, the constituent particles are free to move and there is free space available for the particles to move freely.
Due to this the degree of disorders is very high.
Hence, it has the highest entropy.

So, option D is correct.

Note: Ice and snow are in a solid state. The constituent particles are not free to move due to their tightly packed and ordered structure. Thus, ice and snow have the least entropy.
Water vapours on the other hand have plenty of free space and constituent particles are free to move. It has the highest entropy due to its high degree of disorders.