Indicate which of the following processes are reversible.
(a) Nitrogen and oxygen gases diffuse to give a homogeneous mixture.
(b) Ice sublimes at −5°C and 1.0 atm.
(c) Energy as heat is transferred to the surroundings from a mixture of ice and water at 0°C, causing more ice to form.
(d) Bromine evaporates and the gaseous molecules diffuse into the atmosphere.