Change in entropy for an ideal gas in a reversible isothermal process is given by:

Match the following:

List-$I$	List-$II$
$(A) \Delta U = W_{ad}$	$I.$ Isothermal reversible expansion
$(B) \Delta U = q - W$	$II.$ Wall is adiabatic
$(C) \Delta U = -q$	$III.$ Thermally conducting walls
$(D) \Delta U = 0$	$IV.$ Isolated system
	$V.$ Closed system

The correct answer is

An ideal gas undergoes a reversible cyclic process as shown in the figure. The work done in this process is: (in $,V_1P_1$)

Fill in the blanks given below:
$(i)$ The law of thermodynamics is actually the law of ......... .
$(ii)$ $A$ thermometer measures temperature according to the ......... law of thermodynamics.
$(iii)$ The foundation of thermochemistry is based on the ......... law of thermodynamics.
$(iv)$ The amount of heat required to raise the temperature of a substance by $1^{\circ}C$ is called the ......... of that substance.

The $\Delta H$ for vaporisation of a liquid is $20 \, kJ/mol$. Assuming ideal behaviour,the change in internal energy for the vaporisation of $1 \, mole$ of the liquid at $60^{\circ} C$ and $1 \, bar$ is close to $.... \, kJ/mol$

Consider the following data for the reaction $X_2(g) + Y_2(g) \rightleftharpoons 2XY(g)$ at $600 \ K$. The $\Delta_r G^\circ$ (in $kJ \ mol^{-1}$) for the reaction is:

Compound	$\Delta_f H^\circ$ $(kJ \ mol^{-1})$	$S^\circ$ $(J \ mol^{-1} \ K^{-1})$
$XY(g)$	$42$	$200$
$X_2(g)$	$8$	$140$
$Y_2(g)$	$80$	$250$