One mole of Argon is heated using $PV^{5/2} = \text{constant}$. By what amount is heat absorbed during the process,when the temperature changes by $\Delta T = 26 \ K$ (in $J$)? (Take $R = 8.314 \ J \ mol^{-1} K^{-1}$)

Calculate $\Delta H_f^o$ of $SiH_2$ from the following reactions:
$Si_2H_{6(g)} + H_{2(g)} \to 2SiH_{4(g)}, \Delta H = -11.7 \ kJ/mol$
$SiH_{4(g)} \to SiH_{2(g)} + H_{2(g)}, \Delta H = +239.7 \ kJ/mol$
$\Delta H_f^o(Si_2H_{6(g)}) = 80.3 \ kJ/mol$

What is the difference between $\Delta H$ and $\Delta U$ for the combustion of methane at $25\,^oC$?

For the reaction $2Cl_{(g)} \rightarrow Cl_{2(g)}$,the signs of $\Delta H$ and $\Delta S$ are respectively:

Consider the following statements:
Statement-$I$: Both internal energy $(U)$ and work $(w)$ are state functions.
Statement-$II$: During the free expansion of an ideal gas into vacuum,the work done is zero.
The correct answer is:

How much energy in $kJ$ is required to convert $54 \ g$ of ice at $0 \ ^\circ C$ to water at $27 \ ^\circ C$? $\left( \Delta H_{fusion} = 6.01 \ kJ \ mol^{-1}, C_{p(liquid)} = 4.18 \ J \ K^{-1} \ g^{-1} \right)$