Internal energy of an ideal gas increases in:

During compression of a spring,the work done is $10 \ kJ$ and $2 \ kJ$ escaped to the surroundings as heat. The change in internal energy,$\Delta U$ (in $kJ$),is

When a gas undergoes adiabatic expansion,it cools down because:

An ideal gas,$\overline{C}_{V} = \frac{5}{2} R$,is expanded adiabatically against a constant pressure of $1 \ atm$ until it doubles in volume. If the initial temperature and pressure are $298 \ K$ and $5 \ atm$,respectively,then the final temperature is . . . . . . $K$ (nearest integer). [$\overline{C}_{V}$ is the molar heat capacity at constant volume]

What is the change in internal energy if a system gains $x \ J$ of heat and $y \ J$ of work is done on it?

Assertion : For a reaction $2NH_{3(g)} \to N_{2(g)} + 3H_{2(g)}$ ; $\Delta H > \Delta E$.
Reason : Enthalpy change is always greater than internal energy change.