The heat of vaporisation and heat of fusion of $H_2O$ are $540 \, cal/g$ and $80 \, cal/g$. The ratio of $\frac{\Delta S_{vap}}{\Delta S_{fusion}}$ for water is :-

The heats of combustion of $C_{(s)}$,$H_{2(g)}$,and $C_{2}H_{6(g)}$ are $-x_{1}$,$-x_{2}$,and $-x_{3}$ respectively. The heat of formation of $C_{2}H_{6(g)}$ is:

If the standard enthalpy change $\left(\Delta_{r} H^{\theta}\right)$ for a certain reaction at $298 \ K$ and constant pressure is $-1860 \ kJ \ mol^{-1}$,and the standard entropy change $\left(\Delta_{\text{sys}} S^{\theta}\right)$ of the same reaction is $-550 \ J \ K^{-1} \ mol^{-1}$,which one of the following statements is correct?

The heat change for the following reaction at $298 \ K$ and at constant pressure is $+ 7.3 \ kcal$. $A_2B_{(s)} \to 2A_{(s)} + 1/2 \ B_{2(g)}$,$\Delta H = + 7.3 \ kcal$. The heat change at constant volume would be

$500 \ J$ of energy is transferred as heat to $0.5 \ mol$ of Argon gas at $298 \ K$ and $1.00 \ atm$. The final temperature and the change in internal energy respectively are $:$ Given $: R = 8.3 \ J \ K^{-1} \ mol^{-1}$

For irreversible expansion of an ideal gas under isothermal condition,the correct option is :