# How can I find specific heat in thermochemistry of phase of changes?

Nov 21, 2015

The equation for a phase change is

$q = m \cdot H {\Delta}_{f}$

For a phase change you don't need the specific heat, just the heat of formation (which should be given to you. If not they are easy to find in your textbook or online).

However, you do need the specif heat when you are heating or cooling a substance within a phase (solid, liquid or gas). That equation looks like this:

$q = m {C}_{s} \Delta T$