Which of the following regarding the said processes is (are) correct?

Options

A. Expansion of an ideal gas against vaccum is always reversible
B. A spontaneous proces is always irreversible
C. In a reversible thermodynamic process, system always remains in equilibrium with surroundings
D. If a system containing ideal gas in a piston udergoes expansion from a given initial state to the same final volume,the surroundings loses more heat if expansion is carried out irreversibly rather reversibly

Answer

B, C, D

Explanation

(A) Expansion of an ideal gas against vaccum is an irreversible process.
(B) Spontaneous process is always irreversible
( C) As per defintion of reversible process.
(D) If expansion is carried out reversibly, system will do work and hence, it will absorb more that from the surroundings.