Latent heat

$Q_{lat} = mL_p$ where $L_p$ is the specific latent heat at constant pressure $[J/kg]$. There is no $\Delta T$, as the temperature doesn’t change during the phase change.

When the exchange of heat changes the phase of the body or system, this heat is called latent heat. The opposite is sensible heat. During a phase change, the added heat is used to break the bonds between molecules instead of making them move faster, so the temperature stays constant. For example, when water boils and turns into steam, the measured temperature stays the same.