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

Calculate the change in enthalpy when $39 \ g$ of acetylene is completely burnt with oxygen,given that the enthalpy of combustion of acetylene is $1300 \ kJ \ mol^{-1}$. (in $kJ$)

The heat of neutralisation of $NH_4OH$ and $HCl$ is:

The heat of reaction does not depend upon

According to Hess's Law,the enthalpy change of a reaction depends on which of the following?

If the standard enthalpy change $\left(\Delta_{r} H^\theta\right)$ for the reaction $H_{2(g)} + Br_{2(l)} \rightarrow 2 HBr_{(g)}$ is $-72.8 \ kJ$,the standard enthalpy of formation $\left(\Delta_{f} H^\theta\right)$ of $HBr_{(g)}$ (in $kJ \ mol^{-1}$) is