Which of the following symbols represents the heat of reaction at constant volume?

The law of $Lavoisier$ and $Laplace$ illustrates:

$A$ certain mass of a gas was brought from state $A$ to $B$ by following three different paths, namely $1$, $2$ and $3$, respectively. Which of the following relations is correct for the work done?

Out of molar entropy $(I)$,specific volume $(II)$,heat capacity $(III)$ and volume $(IV)$,which are extensive properties?

For the isothermal reversible expansion of an ideal gas,which of the following is correct?

Which of the following statements is not correct?