What is the change in internal energy if a system does $140 \ kJ$ of work on the surroundings and $40 \ kJ$ of heat is added to the system (in $kJ$)?

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

$A$ heat engine absorbs heat $Q_1$ at temperature $T_1$ and heat $Q_2$ at temperature $T_2$. Work done by the engine is $(Q_1 + Q_2)$. This data

For water $\Delta_{vap} H = 41 \ kJ \ mol^{-1}$ at $373 \ K$ and $1 \ bar$ pressure. Assuming that water vapour is an ideal gas that occupies a much larger volume than liquid water,the internal energy change during evaporation of water is $...... \ kJ \ mol^{-1}$.
[Use: $R = 8.3 \ J \ mol^{-1} \ K^{-1}$]

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?

Identify the reaction for which $\Delta H \neq \Delta E$ :