List the characteristics of entropy.

Explanation

Characteristics of entropy:
(i)Entropy is a thermodynamic state function that is a measure of the randomness or disorderliness of the system .
(ii)In general, the entropy of gaseous system is greater than liquids and greater The symbol of entropy is S.
(iii)Entropy is defined as "for a reversible change taking place at a constant temperature (T), the change in entropy `(DeltaS)` of the system is equal to heat energy absorbed or evolved (q) by the system divided by the constant temperature (T).
`DeltaS_"sys" =q_"rev"/T`
(iv)If heat is absorbed , then `DeltaS` is positive and there will be increase in entropy . If heat is evolved , `DeltaS` is negative and there is a decrease in entropy .
(v)The change in entropy of a process represented by `DeltaS` and is given by the equation,
`DeltaS_"sys" =S_f-S_i`
(vi)If `S_f > S_i , DeltaS` is positive , the reaction is spontaneous and reversible .
If `S_f lt S_i , DeltaS` is negative , the reaction is non-spontaneous and irreversible .
(vii) Unit of entropy :SI unit of entropy is `J K^(-1)`