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 $kJ$?

The reaction of cyanamide,$NH_{2}CN_{(s)}$ with oxygen was run in a bomb calorimeter and $\Delta U$ was found to be $-742.24 \ kJ \ mol^{-1}$. The magnitude of $\Delta H_{298}$ for the reaction
$NH_{2}CN_{(s)} + \frac{3}{2} O_{2(g)} \rightarrow N_{2(g)} + CO_{2(g)} + H_{2}O_{(l)}$
is $............ \ kJ$. (Rounded off to the nearest integer)
[Assume ideal gases and $R = 8.314 \ J \ mol^{-1} K^{-1}$]

For the gas phase reaction,$PCl_{5(g)} \rightleftharpoons PCl_{3(g)} + Cl_{2(g)}$,which of the following conditions are correct?

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.

$A$ pure substance (solid,liquid,or gas) of constant composition is taken in a closed container. Select the correct plot if pressure is applied at constant temperature in the absence of non-expansion work.

What is the enthalpy of vaporization of ethanol in $kJ/mol$? Given: boiling point $(b.p.)$ = $79.5 \, ^\circ C$ and entropy change $(\Delta S_{vap})$ = $109.8 \, J K^{-1} mol^{-1}$.