The heat change for the following reaction ${\mathrm{C}}_{\left(\mathrm{s}\right)}$ $+2{\mathrm{ }\mathrm{S}}_{\left(\mathrm{s}\right)}\to {\mathrm{CS}}_{2\left(l\right)}$ is known as

Given: We need to find The heat change for the following reaction ${\mathrm{C}}_{\left(\mathrm{s}\right)}$ $+2{\mathrm{ }\mathrm{S}}_{\left(\mathrm{s}\right)}\to {\mathrm{CS}}_{2\left(l\right)}$.

Concept Used: Exothermic and endothermic reactions

Explanation: ${\mathrm{C}}_{\left(\mathrm{s}\right)}+2{ \mathrm{S}}_{\left(\mathrm{s}\right)}\to {\mathrm{CS}}_{2\left(\mathrm{l}\right)}$

In the given reaction, 1 mole of ${\mathrm{CS}}_2$ is formed by its constituent elements, hence the heat change for the given reaction is known as heat of formation.

In chemistry and thermodynamics, the standard enthalpy of formation or standard heat of the formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements in their reference state, with all substances in their standard states.

Hence the correct answer is (A) Heat of formation of ${\mathrm{CS}}_2$.