$1 \ cc$ of water at its boiling point $(100^{\circ} \ C)$ is converted into steam by supplying $540 \ \text{calories}$ of heat. The volume of steam is $1671 \ cc$. If atmospheric pressure is $1.013 \times 10^5 \ \text{Nm}^{-2}$ and $J = 4.18 \ \text{joule/cal}$, the approximate value of heat required to overcome the molecular attraction is ........ $\text{cal}$.

For a thermodynamic process $\delta Q = -50 \text{ calorie}$ and $W = -20 \text{ calorie}$. If the initial internal energy is $-30 \text{ calorie}$,then the final internal energy will be ....... $\text{calorie}$.

$1.00 \ kg$ of liquid water at $100^{\circ} C$ undergoes a phase change into steam at $100^{\circ} C$ at $1.0 \ atm$ (take it to be $1.00 \times 10^5 \ Pa$). The initial volume of the liquid water was $1.00 \times 10^{-3} \ m^3$ which is changed to $2.001 \ m^3$ of steam. Find the change in the internal energy of the system. [Use heat of vaporization $\simeq 2000 \ kJ \ kg^{-1}$] (in $kJ$)

In a thermodynamic process,the pressure of a fixed mass of a gas is changed in such a manner that the gas releases $30 \ J$ of heat and $10 \ J$ of work is done on the gas. If the initial internal energy of the gas was $30 \ J$,then the final internal energy will be ........ $J$.

When the amount of work done is $333 \ cal$ and the change in internal energy is $167 \ cal$,then the heat supplied is ....... $cal$.

$A$ system is given $300$ calories of heat and it does $600$ joules of work. How much does the internal energy of the system change in this process? $(1 \text{ calorie} = 4.18 \text{ joules})$