Hess's law

Given the following data: $\ce{CaO(s) + CO2(g) -> CaCO3(s)}$ $\Delta H = -p\ \mathrm{kJ}$ $\ce{2Ca(s) + O2(g) -> 2CaO(s)}$ $\Delta H = -q\ \mathrm{kJ}$ $\ce{2CaCO3(s) -> 2Ca(s) + 2C(s) + 3O2(g)}$ $\Delta H = +r\ \mathrm{kJ}$ What is the $\Delta H$ of the…

The standard enthalpy changes of two reactions are given below. $\ce{N2(g) + O2(g) -> 2NO(g)}$ $\Delta H^\ominus = x\ \mathrm{kJ\,mol^{-1}}$ $\ce{2NO(g) + O2(g) -> 2NO2(g)}$ $\Delta H^\ominus = y\ \mathrm{kJ\,mol^{-1}}$ What is $\Delta H^\ominus$, in…

Methanol can be synthesized from carbon monoxide and hydrogen: $\ce{CO(g) + 2H2(g) -> CH3OH(l)}$ Reaction $\Delta H$ / $\mathrm{kJ\,mol^{-1}}$ $\ce{CH3OH(g) + 3/2 O2(g) -> CO2(g) + 2H2O(l)}$ $-764$ $\ce{CO(g) + 1/2 O2(g) -> CO2(g)}$ $-283$…