$4 \ g$ of $NH_4NO_3$ were dissolved in $196 \ g$ of water at constant pressure in a calorimeter with a heat capacity of $160 \ J \ K^{-1}$. The temperature fell by $1.3 \ K$. The specific heat of the solution is $4.2 \ J \ K^{-1} \ g^{-1}$. The enthalpy of solution of $NH_4NO_3$ is $......$ $kJ \ mol^{-1}$.

For a pure substance,if $T_B$ is the melting point and $T_A$ is the freezing point,which graph correctly represents the relationship between the change in entropy $(\Delta S)$ and temperature $(T)$?

The number of endothermic process/es from the following is:
$A. I_{2(g)} \rightarrow 2I_{(g)}$
$B. HCl_{(g)} \rightarrow H_{(g)} + Cl_{(g)}$
$C. H_2O_{(l)} \rightarrow H_2O_{(g)}$
$D. C_{(s)} + O_{2(g)} \rightarrow CO_{2(g)}$
$E. \text{Dissolution of ammonium chloride in water}$

$A$ gas is reversibly expanded from the same initial state to the same final volume using isobaric,isothermal,and adiabatic processes. The correct order of the work done by the system on the surroundings in the three different methods is

One mole of an ideal gas at $900 \ K$ undergoes two reversible processes,$I$ followed by $II$,as shown in the graph. If the work done by the gas in the two processes is the same,the value of $\ln \frac{V_3}{V_2}$ is. . . . . . . . ($U$: internal energy,$S$: entropy,$p$: pressure,$V$: volume,$R$: gas constant). (Given: molar heat capacity at constant volume,$C_{V, m}$ of the gas is $\frac{5}{2} R$)

Which of the following relations is not correct?