For the combustion reaction $2C_8H_{18}(g) + 25O_2(g) \rightarrow 16CO_2(g) + 18H_2O(g)$,what are the signs of $\Delta H$,$\Delta S$,and $\Delta G$?

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 $.... \, kJ/mol$

The enthalpies of combustion of carbon and carbon monoxide are $-393.5 \, kJ \, mol^{-1}$ and $-283 \, kJ \, mol^{-1}$ respectively. The enthalpy of formation of carbon monoxide per mole is $....... \, kJ \, mol^{-1}$. (in $.5$)

The heat of combustion of $CO$ at $290 \ K$ and constant volume is $-280.5 \ kJ$. What will be the heat of combustion at constant pressure in $kJ$?

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 ............. $K$.

The molar heats of fusion and vaporisation of benzene are $10.9$ and $31.0 \ kJ \ mol^{-1}$ respectively. The changes in entropy for the solid $\rightarrow$ liquid and liquid $\rightarrow$ vapour transitions for benzene are $x$ and $y \ JK^{-1} \ mol^{-1}$,respectively. The value of $(y-x)$ (in $JK^{-1} \ mol^{-1}$) is (At $1 \ atm$,benzene melts at $5.5^{\circ} C$ and boils at $80^{\circ} C$).