Select the factor that affects the heat of reaction which is based on Kirchoff’s equation

The correct option is Temperature.

Step-by-Step Explanation:

Kirchhoff's equation relates the variation in the heat of a chemical reaction (enthalpy of reaction) directly to the change in temperature of the system. According to thermodynamics, the heat of reaction at constant pressure (${\mathrm{\Delta H}}_{}$) or constant volume (${\mathrm{\Delta U}}_{}$) changes when the temperature changes.

The mathematical formulation of Kirchhoff's law at constant pressure is expressed as:

$\frac{d\left(\mathrm{\Delta H}\right)}{dT}={\mathrm{\Delta C}}_p$

Where:

• $\mathrm{\Delta H}$ represents the change in enthalpy (heat of reaction at constant pressure).
• $T$ represents the absolute temperature.
• ${\mathrm{\Delta C}}_p$ is the difference in heat capacities at constant pressure between the products and the reactants (${\mathrm{\Delta C}}_p=\sum C_{\text{p, products}}-\sum C_{\text{p, reactants}}$).

Similarly, at constant volume, the equation is written as:

$\frac{d\left(\mathrm{\Delta U}\right)}{dT}={\mathrm{\Delta C}}_v$

Where $\mathrm{\Delta U}$ is the heat of reaction at constant volume and ${\mathrm{\Delta C}}_v$ is the difference in heat capacities at constant volume.

Since both forms of Kirchhoff's equation show how the enthalpy or internal energy change of a reaction varies with temperature ($T$), Temperature is the key factor affecting the heat of reaction based on Kirchhoff's equation.