The entropy change involved in the isothermal reversible expansion of $2 \, \text{mole}$ of an ideal gas from a volume of $10 \, dm^3$ to a volume of $100 \, dm^3$ at $27 \, ^oC$ is : .............. $J \, K^{-1}$

One mole of an ideal diatomic gas $(C_V = 5 \ cal)$ was transformed from initial $25 \ ^{\circ}C$ and $1 \ L$ to the state when temperature is $100 \ ^{\circ}C$ and volume $10 \ L$. The entropy change of the process can be expressed as $(R = 2 \ cal / mol \cdot K)$ :-

For the transformation $C(\text{graphite}) \rightarrow C(\text{diamond})$,$\Delta S$ is .......

The entropy change for the expansion of $2 \, \text{mol}$ of an ideal gas from $2 \, \text{L}$ to $20 \, \text{L}$ at a temperature of $27 \, ^oC$ is ...... $(R = 2 \, \text{cal/mol K})$

One mole of an ideal gas at $350 \, K$ is in a $2.0 \, L$ vessel with thermally conducting walls,which are in contact with the surroundings. It undergoes isothermal expansion from $2.0 \, L$ to $3.0 \, L$ against a constant external pressure of $4 \, atm$. The change in entropy of the surroundings $(\Delta S_{surr})$ is $...... \, J \, K^{-1}$ (Nearest integer). Given: $R = 8.314 \, J \, K^{-1} \, mol^{-1}$.

$A$ reversible adiabatic process is one in which: