Which among the following statements is/are incorrect regarding real gases?
(i) Their compressibility factor is never equal to unity (Z $$\ne$$ 1).
(ii) The deviations from ideal behaviour are less at low pressures and high temperatures.
(iii) Intermolecular forces among gas molecules are equal to zero.
(iv) They obey van der Waals’ equation, $$pV = nRT$$
Which among the following species does not show disproportionation reaction?
An alloy of metals X and Y weighs 12 g and contains atoms X and Y in the ratio of 2 : 5. The percentage of metal X in the alloy is 20 by mass. If the atomic mass of X is 40 amu what is the atomic mass of metal Y ?
For the reaction, $$\mathrm{H}_2 \mathrm{O}(l) \longrightarrow \mathrm{H}_2 \mathrm{O}(\mathrm{g})$$ at $$T=100^{\circ} \mathrm{C}$$ and $$p=1 \mathrm{~atm}$$, choose the correct option.