Calculate $\Delta U$ if $2 \ kJ$ heat is released and $10 \ kJ$ of work is done on the system. (in $kJ$)

Work done in vaporisation of one mole of water at $373 \ K$ and the pressure of $1 \ atm$ is approximately (for ideal gas)......$J$

The volume of an ideal gas contracts from $10.0 \ L$ to $2.0 \ L$ under an applied pressure of $2.0 \ atm$. During contraction,the system also evolved $900 \ J$ of heat. The change in internal energy (in $J$) involved in the system is $(1 \ L \ atm = 101.3 \ J)$:

$A$ system gives out $x \ J$ of heat and does $y \ J$ of work on its surroundings. What is the internal energy change?

When a system expands under adiabatic conditions,what happens to its internal energy?

During an isothermal process,which of the following is true?