For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter,$\Delta U$ and $w$ correspond to

Consider the $P-V$ (pressure-volume) diagram given below,where an ideal gas is reversibly converted from state $X$ to state $Y$. Among the following,which is the correct $T-S$ (temperature-entropy) diagram corresponding to this process?

The heats of combustion $\Delta H$ of $CH_4$,$C_2H_6$,$C_2H_4$,and $C_2H_2$ gases are $-212.8$,$-373.0$,$-337.0$,and $-310.5 \ kcal$ respectively at the same temperature. Which of these gases is the best fuel?

At $298 \ K$,$\Delta_r U^{\ominus}$ and $\Delta_r S^{\ominus}$ for the following reaction are $-10.5 \ kJ$ and $+44.1 \ J \ K^{-1} \ mol^{-1}$ respectively. The reaction is: $2 \ X_{(g)} + Y_{(g)} \longrightarrow 2 \ Z_{(g)}$. What is $\Delta_r G^{\ominus}$ (in $kJ$) for this reaction? $(R = 8.314 \ J \ K^{-1} \ mol^{-1})$

Standard entropies of $X_2, Y_2$ and $XY_3$ are $60, 40$ and $50 \ J \ K^{-1} \ mol^{-1}$ respectively. For the reaction $\frac{1}{2} X_2 + \frac{3}{2} Y_2 \rightleftharpoons XY_3, \Delta H = -30 \ kJ$,to be at equilibrium,the temperature should be ............. $K$.

For the process $H_2O_{(l)} \rightarrow H_2O_{(g)}$ at $100^{\circ}C$ and $1 \ atm$ pressure,which of the following is true?