$2.5 \ kJ$ of work is done on the system and it releases $1500 \ J$ of heat. What is the change in internal energy (in $J$)?

If a gas expands adiabatically from $1 \, L$ to $12 \, L$ against a constant external pressure of $0.75 \, atm$,the $\Delta U$ of the gas is .... $J$. (in $.9$)

An engine absorbs heat $Q_1$ at temperature $T_1$ and heat $Q_2$ at temperature $T_2$. The work done by the engine is given as $W = Q_1 + Q_2$. Which of the following statements is correct?

Calculate the quantity of heat released from a system when $2 \text{ moles}$ of an ideal gas are compressed isothermally from a volume of $25 \text{ dm}^3$ to $10 \text{ dm}^3$ at a constant external pressure of $4 \text{ bar}$. (in $\text{ kJ}$)

For a reaction,$A_{(g)} \to A_{(l)}$; $\Delta H = -3RT$. The correct statement for the reaction is

$A$ gas undergoes a change from state $A$ to state $B$. In this process,the heat absorbed and work done by the gas are $5\, J$ and $8\, J$,respectively. Now,the gas is brought back to $A$ by another process during which $3\, J$ of heat is evolved. In this reverse process of $B$ to $A$: