Question

The entropy of a crystalline substance at absolute zero on the basis of third law of thermodynamics should be taken as:

• A. $100$
• B. $50$
• C. zero
• D. different for different substances

Answer 1

The correct option is C zero

The third law of thermodynamics was formulated by Nernst. It states that, "The entropy of a perfactly crystalline substance at absolute zero or zero kelvin is taken as zero".

$\Delta S={\int }_0^T{C}_{P}d\left(lnT\right)=2.303{\int }_0^T{C}_{P}d\left(logT\right)$

The $\Delta S$ is calculate by above formula of pure substance at different temperature.