Hi.

I'm studying the refrigeration cycle and I know the basic thermodynamics equations (enthalpy, entropy...).
And I have a doubt.

Why is the compression considered approximately isoentropic and the expansion isoenthalpic and no the other way? (the compression isoenthalpic and the expansion isoentropic).
In the basic process (without extra efficiency factors or losses) I think both processes are adiabatic (if done slowly to be reversible).

regards.