$A$ certain system is exothermic by $260 \ kJ$ and does $10 \ kJ$ of work. What is the change in internal energy (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?

For combustion of one mole of magnesium in an open container at $300 \ K$ and $1 \ bar$ pressure,$\Delta_{C}H^{\ominus} = -601.70 \ kJ \ mol^{-1}$,the magnitude of change in internal energy for the reaction is $.... \ kJ$. (Nearest integer)
(Given : $R = 8.3 \ J \ K^{-1} \ mol^{-1}$ )

If one mole of ammonia and one mole of hydrogen chloride are mixed in a closed container to form ammonium chloride gas,then

For the reaction $N_{2(g)} + 3H_{2(g)} \rightarrow 2NH_{3(g)}$,the relationship between $\Delta H$ and $\Delta U$ is:

$A$ sample of gas expands against a constant external pressure of $1 \ atm$ from a volume of $2 \ L$ to $12 \ L$. During this process,it absorbs $600 \ J$ of heat. Calculate $\Delta E$ of the system.