Question

What is the difference between specific heat and enthalpy of formation?

Answer 1

In thermodynamics, enthalpy is a property of a substance which is defined as the sum of its internal energy and product of its pressure and volume and specific heat represents the rise in temperature of liquid due to heat transfer to the system.

Complete answer:
Although specific heat and enthalpy of formation are two different terms but the difference between these terms can be summarized as per following table:

| Specific heat| Enthalpy of formation
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Definition| The amount of heat required to raise the temperature of one gram of a substance by one-degree Celsius.| The amount of heat evolved or absorbed when one mole of a compound is formed from its constituent elements, given that each element is present in its standard physical state.
Units| It is usually expressed in calories or joule per gram per degree Celsius $\left[ {J{{\left( {g{\;^o}C} \right)}^{ - 1}}} \right]$ .| It is usually expressed in kilojoule per mole $kJmo{l^{ - 1}}$ .
Formula| $c = \dfrac{Q}{{m\Delta T}}$ , where Q represents heat energy, m represents mass and $\Delta T$ represents change in temperature.| $\Delta H_f^o = \sum n H_{f({\text{products)}}}^o - \sum m H_{f({\text{reactants)}}}^o$ , where m and n represent the coefficient of reactants and products of the balanced chemical reaction respectively.
Property| It is an intensive property i.e., it does not depend on the amount of matter present.| It is an extensive property i.e., it depends on the amount of matter present in the reaction.

Note:
It is important to note that students might get confused with terms specific heat and heat capacity. Remember that specific heat is the amount of heat per unit mass needed to raise the temperature by one unit whereas heat capacity is the amount of heat needed to raise the temperature of the entire body by one unit.