Which from following thermodynamic properties is a path function?

Calculate the PV type of work for the following reaction at 1 bar pressure.

$$\mathrm{\mathop {{C_3}{H_{6(g)}}}\limits_{(150\,mL)} + \mathop {HC{l_{(g)}}}\limits_{(150\,mL)} \buildrel {} \over \longrightarrow \mathop {{C_3}{H_7}C{l_{(g)}}}\limits_{(150\,mL)}}$$

If enthalpy change for following reaction at $$300 \mathrm{~K}$$ is $$+7 \mathrm{~kJ} \mathrm{~mol}^{-1}$$ find the entropy change of surrounding?

$$\mathrm{H}_2 \mathrm{O}_{(\mathrm{s})} \longrightarrow \mathrm{H}_2 \mathrm{O}_{(\ell)}$$

Calculate $$\Delta \mathrm{H}$$ for following reaction, at $$25{ }^{\circ} \mathrm{C}$$.

$$\mathrm{NH}_2 \mathrm{CN}_{(\mathrm{g})}+\frac{3}{2} \mathrm{O}_{2(\mathrm{~g})} \longrightarrow \mathrm{N}_{2(\mathrm{~g})}+\mathrm{CO}_{2(\mathrm{~g})}+\mathrm{H}_2 \mathrm{O}_{(\mathrm{g})}$$

$$(\Delta \mathrm{U}=-740.5 \mathrm{~kJ}, \mathrm{R}=8.314 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1})$$