Mischmetal is an alloy consisting mainly of :

The average molar mass of chlorine is 35.5 g mol^–1. The ratio of ³⁵Cl to ³⁷Cl in naturally occuring chlorine is close to :

The correct match between Item-I (starting material) and Item-II (reagent) for the preparation of benzaldehyde is :

Item-I	Item-II
(I) Benzene	(P) HCl and SnCl2, H3O+
(II) Benzonitrile	(Q) H2, Pd-BaSO4, S and quinoline
(III) Benzoyl Chloride	(R) CO, HCl and AlCl3

For a reaction,
4M(s) + nO₂(g) $$ \to $$ 2M₂O_n(s)
the free energy change is plotted as a function of temperature. The temperature below which the oxide is stable could be inferred from the plot as the point at which :