The heat $Q$ for a reaction at constant volume is equal to

For which of the following reactions,$\Delta H$ is equal to $\Delta U$ ?

Among the following, which are extensive variables?

Which of the following is not a state function of a thermodynamic system?

For a chemical reaction,when does $\Delta H = \Delta U$ occur?

$1 \, mol$ of an ideal gas is compressed reversibly at a constant temperature of $27 \, ^oC$ from $1 \, bar$ to $4 \, bar$. Calculate the work done in $kJ$.