Which of the following is the correct expression of the first law of thermodynamics for adiabatic processes?

When a certain volume of gas expands against a constant external pressure of $2.40 \times 10^5 \ Pa$ at $300 \ K$ to a final volume of $2.2 \times 10^{-3} \ m^3$. If the work obtained is $-0.048 \ kJ$,what is the initial volume of the gas?

If a system absorbs $30 \ kJ$ of heat and performs $12 \ kJ$ of work on the surroundings,what is the increase in internal energy of the system (in $kJ$)?

For the reaction $PCl_{5(g)} \to PCl_{3(g)} + Cl_{2(g)}$,which of the following relations is correct?

In an adiabatic expansion of an ideal gas,which of the following relations holds true?

An ideal gas is subjected to a cyclic process involving four thermodynamic states. The amounts of heat $(Q)$ and work $(W)$ involved in each of these processes are:
$Q_1 = 6000 \, J, Q_2 = -5500 \, J, Q_3 = -3000 \, J, Q_4 = 3500 \, J$
$W_1 = 2500 \, J, W_2 = -1000 \, J, W_3 = -1200 \, J, W_4 = x \, J$
The ratio of the net work done by the gas to the total heat absorbed by the gas is $\eta$. The values of $|x|$ and $\eta$ respectively are: