Which of the following relationships is valid only for reversible processes undergone by a closed system of simple compressible substance (neglect changes in kinetic and potential energy?)
(A) QdU W δδ=+
(B) Tds dU pdν =+
(C) Tds dU W δ =+
(D) QdUpd δν=+
Water has a critical specific volume of 0.003155 / mkg^3. A closed and rigid steel tank of volume 0.025 m
contains a mixture of water and steam at 0.1 MPa. The mass of the mixture is 10 kg. The tank is now slowly heated.
The liquid level inside the tank.
(A) will rise
(B) will fall
(C) will remain constant
(D) may rise or fall depending on the amount of heat transferred