$A$ system receives $100 \ cal$ of heat,and at the same time,$50 \ cal$ of work is done by the system. Calculate the change in internal energy. (in $cal$)

For a reaction,$A_{(g)} \to A_{(l)}$; $\Delta H = -3RT$. The correct statement for the reaction is

$A$ system receives $224 \ J$ of heat and does $156 \ J$ of work. Calculate the change in internal energy. (in $J$)

$A$ mixture of $2 \ mol$ of carbon monoxide and $1 \ mol$ of oxygen in a closed vessel is ignited to convert the carbon monoxide to carbon dioxide. If $\Delta H$ is the enthalpy change and $\Delta E$ is the change in internal energy,then:

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.

For $1 \, \text{mol}$ of an ideal gas,isothermal expansion occurs from $1 \, \text{L}$ to $10 \, \text{L}$ in a vacuum at $300 \, \text{K}$. What is the value of $\Delta U$ for this process? $(R = 2 \, \text{cal} \, \text{K}^{-1} \, \text{mol}^{-1})$