The process that is NOT endothermic in nature is :

Five moles of an ideal gas at 1 bar and 298 K is expanded into vacuum to double the volume. The work done is :

Consider the following equations :
2Fe²⁺ + H₂O₂ $$ \to $$ xA + yB
(in basic medium)
2MnO₄^- + 6H⁺ + 5H₂O₂ $$ \to $$ x'C + y'D + z'E
(in acidic medium)
The sum of the stoichiometric coefficients x, y, x', y', and z' for products A, B, C, D and E, respectively, is ______.

The osmotic pressure of a solution of NaCl is 0.10 atm and that of a glucose solution is 0.20 atm. The osmotic pressure of a solution formed by mixing 1 L of the sodium chloride solution with 2 L of
the glucose solution is x $$ \times $$ 10^–3 atm. x is _____. (nearest integer)