The enthalpy of solution of $NaOH$ (solid) in water is $-41.6 \ kJ \ mol^{-1}$. When $NaOH$ is dissolved in water,the temperature of the water

From the given data at $298 \, K$:
$\Delta H_f^o [CO_2, g] = -394 \, kJ/mol$
$\Delta H_f^o [H_2O, l] = -286 \, kJ/mol$
$\Delta H_f^o [propene, g] = 20 \, kJ/mol$
$cyclopropane (g) \to propene (g)$; $\Delta H^o_{isomerisation} = -33 \, kJ/mol$.
Calculate $\Delta H^o_{combustion} [cyclopropane, g]$.
$...... \, kJ/mol$

In the reaction: $H_2 + Cl_2 \to 2HCl, \Delta H = -194 \ kJ$. The heat of formation of $HCl$ is ........ $kJ$.

Given that the bond energy of hydrogen-hydrogen bond is $436 \ kJ/mol$,that of hydrogen-oxygen bond is $464 \ kJ/mol$,and those in oxygen molecules $496 \ kJ/mol$,what is the approximate heat of reaction for $2H_2 + O_2 \longrightarrow 2H_2O$ ? .....$kJ/mol$

The enthalpies of formation of $N_2O$ and $NO$ are $28$ and $90 \ kJ \ mol^{-1}$ respectively. The enthalpy of the reaction,$2N_2O_{(g)} + O_{2(g)} \to 4NO_{(g)}$ is equal to.....$kJ$

Which of the following equations is used to calculate the standard enthalpy change of a reaction $(\Delta_r H^\circ)$?