For the following sequence of reactions, the correct products are :

Identify correct A, B and C in the reaction sequence given below :

The number of S = O bonds present in sulphurous acid, peroxodisulphuric acid and pyrosulphuric acid, respectively are :

CH₄ is absorbed on 1g charcoal at 0$$^\circ$$C following the Freundlich adsorpiton isotherm 10.0 mL of CH₄ is adsorbed at 100 mm of Hg, whereas 15.0 mL is adsorbed at 200 mm of Hg. The volume of CH₄ adsorbed at 300 mm of Hg is 10^x mL. The value of x is _________ $$\times$$ 10^-2.

(Nearest integer) [Use log₁₀2 = 0.3010, log₁₀3 = 0.4771]