Calculate the amount of methane formed by the liberation of $149.6 \ kJ$ of heat using the following equation:
$C_{(s)} + 2H_{2(g)} \longrightarrow CH_{4(g)} \quad \Delta H = -74.8 \ kJ/mol$ (in $g$)

If $C$ (diamond) $\rightarrow C$ (graphite) $+ X \ kJ \ mol^{-1}$,$C$ (diamond) $+ O_{2(g)} \rightarrow CO_{2(g)} + Y \ kJ \ mol^{-1}$,and $C$ (graphite) $+ O_{2(g)} \rightarrow CO_{2(g)} + Z \ kJ \ mol^{-1}$,at constant temperature,then which of the following relations is correct?

Heat produced in calories by the combustion of one gram of carbon is called

The heat of neutralisation of a strong acid and a strong alkali is $57.0 \, kJ \, mol^{-1}$. The heat released when $0.5 \, mole$ of $HNO_3$ solution is mixed with $0.2 \, mole$ of $KOH$ is $...... \, kJ$.

The value of ${\Delta _f}{H^o}$ for $HgO$ is $-90.5 \, kJ \, mol^{-1}$. The amount of $Hg$ produced thermally from $HgO$ by $1600 \, kJ$ of heat is ......... (in $, kg$)

Calculate the enthalpy change in $kJ$ for the reaction: $2C_{(graphite)} + 2H_{2(g)} \to C_2H_{4(g)}$
$C_{(graphite)} + O_{2(g)} \to CO_{2(g)} \quad \Delta H = -393.5 \ kJ$
$C_2H_{4(g)} + 3O_{2(g)} \to 2CO_{2(g)} + 2H_2O_{(l)} \quad \Delta H = -1410.9 \ kJ$
$H_{2(g)} + 1/2O_{2(g)} \to H_2O_{(l)} \quad \Delta H = -285.8 \ kJ$