The change in internal energy when $20 \,g$ of a gas is heated from $25^{\circ} C$ to $35^{\circ} C$ at constant volume is (Specific heat capacity of the gas at constant volume $C_{v} = 0.2 \,cal \,g^{-1} {}^{\circ} C^{-1}$): (in $\,J$)

In changing the state of a thermodynamic system from state $A$ to state $B$, the heat supplied to the system is $Q$ and the work done by the system is $W$. The change in its internal energy is

The first law of thermodynamics is a special case of which law?

$1 \, kg$ of a gas does $20 \, kJ$ of work and receives $16 \, kJ$ of heat when it is expanded between two states. $A$ second kind of expansion can be found between the initial and final states which requires a heat input of $9 \, kJ$. The work done by the gas in the second expansion is ....... $kJ$.

When a system is taken from state $i$ to a state $f$ along path $iaf$,$Q = 50 \, J$ and $W = 20 \, J$. Along path $ibf$,$Q = 35 \, J$. If $W = -13 \, J$ for the curved return path $fi$,$Q$ for this path is ...... $J$.

$1 \,g$ of water at $100^{\circ} C$ is completely converted into steam at $100^{\circ} C$. $1 \,g$ of steam occupies a volume of $1650 \,cc$. (Neglect the volume of $1 \,g$ of water at $100^{\circ} C$). At the pressure of $10^5 \,N/m^2$, the latent heat of steam is $540 \,cal/g$ $(1 \,calorie = 4.2 \,joule)$. The increase in the internal energy (in joule) is: