The heat of neutralization of a strong acid and a weak base is:

When $50 \ cm^3$ of a strong acid is added to $50 \ cm^3$ of an alkali,the temperature rises by $5 \ ^oC$. If $250 \ cm^3$ of each liquid are mixed,the temperature rise would be $... \ ^oC$.

The standard enthalpy of formation $(\Delta_fH^o)$ at $298 \ K$ for methane,$CH_{4(g)}$ is $-74.8 \ kJ \ mol^{-1}$. The additional information required to determine the average energy for $C-H$ bond formation would be

Using the data provided,calculate the bond energy $(kJ \ mol^{-1})$ of a $C \equiv C$ bond in $C_{2}H_{2}$. (Take the bond energy of a $C-H$ bond as $350 \ kJ \ mol^{-1}$)
$2C_{(s)} + H_{2(g)} \longrightarrow C_{2}H_{2(g)} \quad \Delta H = 225 \ kJ \ mol^{-1}$
$2C_{(s)} \longrightarrow 2C_{(g)} \quad \Delta H = 1410 \ kJ \ mol^{-1}$
$H_{2(g)} \longrightarrow 2H_{(g)} \quad \Delta H = 330 \ kJ \ mol^{-1}$

The absolute enthalpy of neutralisation of the reaction $MgO_{(s)} + 2HCl_{(aq)} \to MgCl_{2(aq)} + H_2O_{(l)}$ will be

The standard heats of combustion of $C_{(s)}$,$S_{(s)}$,and $CS_{2(\ell)}$ are $-393.3 \, kJ \, mol^{-1}$,$-293.72 \, kJ \, mol^{-1}$,and $-1108.76 \, kJ \, mol^{-1}$ respectively. The standard heat of formation of $CS_{2(\ell)}$ in $kJ \, mol^{-1}$ is: