What is the relationship between enthalpy and entropy ?

Enthalpy  (H) is defined as the amount of 

energy released or absorbed during a chemical reaction .
Entropy (S) defines the degree of randomness or disorder

 in a system.
Therefore, there is no direct relationship between entropy

 and enthalpy. However, the free energy (G) regroups both

 terms as:
G = H - T S
where at constant temperature, the change on free energy is 

defined as:
ΔG=ΔH−TΔS.
Therefore, the free energy expression provides a relationship 

between enthalpy and entropy.
Thus, for a system at equilibrium, ΔG=, and then we find

 that  ΔS=TΔH​.