Which equation clearly defines the entrophy change during the isothermal process for a system with m kg of gas at pressure $$P_{1}$$ and the $$volume V_{1}$$, temperature $$T_{1}$$ and the entrophy $$S_{1}$$ is heated to state points of pressure $$P_{2}$$ , Volume $$V_{2}$$ and temperature $$T_{2}$$ and Entrophy $$ S_{2} $$?

A

$$mc_{v} \ln \frac{T_{2}}{T_{1}}$$

B

$$mc_{p} \ln \frac{T_{2}}{T_{1}}$$

C

$$mR\ln \frac{V_{2}}{V{1}}$$

D

$$mc_{v} \left(\frac{n-\gamma}{n-1}\right) \ln \frac{T_{2}}{T_{1}} $$