Question

The entropy change can be calculated by using the expression, $\Delta S = \frac{q_{rev}}{T}$ When water freezes in a glass beaker, choose the correct statement amongst the following:

• A. $\Delta S_{system}$decreases but $\Delta S_{surroundings}$ remains the same.
• B. $\Delta S_{system}$ increases but $\Delta S_{surroundings}$ decreases.
• C. $\Delta S_{system}$ decreases but $\Delta S_{surroundings}$increases.
• D. $\Delta S_{system}$ decreases and $\Delta S_{surroundings}$ also decreases.

Answer 1

Answer: (C)

$\Delta S_{system}$ decreases but $\Delta S_{surroundings}$increases.

Answer 2

: As water freezes from liquid to solid, randomness decreases, i.e. $\Delta S_{system}$ decreases. Heat released during the process, is absorbed by the surrounding hence, $\Delta S_{surroundings}$ increases.