Properties and Property Relations:Identifying States

Quality can only have values between 0 and 1. If one ﬁnds values outside this range, one either has compressed liquid, or superheated vapor.

A state of given temperature T for which another property (v or u or h or s) is known, is compressed liquid for

A state of given pressure p for which another property (v or u or h or s) is known, is compressed liquid for

and it is superheated vapor if

It is a useful exercise to verify the above conditions by means of p-v-, T-s-, and p-T-diagrams!