Question

The total entropy change $\left(△S_{total}\right)$ for the system and the surrounding of a spontaneous process is given by:

• A. $△S_{total}=△S_{system}+△S_{surr}>0$
• B. $△S_{total}=△S_{system}-△S_{surr}>0$
• C. $△S_{system}=△S_{total}+△S_{surr}>0$
• D. $△S_{surr}=△S_{total}-△S_{system}<0$

Answer 1

The correct option is A $△S_{total}=△S_{system}+△S_{surr}>0$

Entropy is a measure of the amount of disorderness present in the system.

For a spontaneous process, $\Delta S_{total}>0$.
As we know, from the second law of thermodynamics,

"All spontaneous processes are irreversible and are accompanied with increase in total entropy (S)".

In simple words, the entropy of an isolated system increases in the course of a spontaneous change.
i.e. $△S_{total}=△S_{system}+△S_{surr}>0$