Mollier diagram and reversible/irreversible process...?

cabellos

I have been looking through past papers in preparation for an exam. Im confused on how to tackle the following question:

Use a Mollier diagram to identify whether the following process is irreversible, reversible or not possible. The process starts from 1.8bar dry saturated (h=2700kJ/kg)

a.) Isentropic heat addition of Q = +100kJ


My initial thoughts are this involves the Clausius inequalities?

Thanks for help with this question