Explain the heat capacity of a substance and write its equation and unit.

(A) The quantity of heat required to warm a given substance depends on its mass $(m)$,the change in temperature $(\Delta T)$,and the nature of the substance.
The change in temperature of a substance,when a given quantity of heat is absorbed or rejected by it,is characterized by a quantity called the heat capacity of that substance.
Heat capacity $(S)$: Heat capacity is defined as the ratio of the heat supplied to a substance $(\Delta Q)$ to the corresponding change in its temperature $(\Delta T)$.
Mathematically,it is expressed as:
$S = \frac{\Delta Q}{\Delta T}$
Where $\Delta Q$ is the amount of heat supplied to the substance to change its temperature from $T$ to $T + \Delta T$.
The value of heat capacity depends on the type of material and its mass. Heat capacity of substances of the same material but different mass can be different.
The $SI$ unit of heat capacity is $J K^{-1}$ or $J/K$.