If $2 \ kJ$ of heat is released from the system and $6 \ kJ$ of work is done on the system,what is the internal energy change $(\Delta U)$ of the system?

$A$ gas expands from a volume of $1 \text{ dm}^3$ to $1.25 \text{ dm}^3$ against a constant external pressure of $1 \text{ bar}$. Calculate the change in internal energy $(\Delta U)$ if $150 \text{ J}$ of heat is supplied to the system. (in $\text{ J}$)

$A$ gas is allowed to expand in an insulated container against a constant external pressure of $10 \ atm$ from an initial volume $4.2 \ L$ to $5.2 \ L$. The change in internal energy $\Delta E$ of the gas will be $:-$

Which of the following equations represents the first law of thermodynamics under isobaric conditions?

$A$ gas undergoes a change from state $A$ to state $B$. In this process,the heat absorbed and work done by the gas are $5\, J$ and $8\, J$,respectively. Now,the gas is brought back to $A$ by another process during which $3\, J$ of heat is evolved. In this reverse process of $B$ to $A$:

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 : $R = 8.3 \ J \ K^{-1} \ mol^{-1}$ )