Freezing point of a 4% aqueous solution of X is equal to freezing point of 12% aqueous solution of Y. If molecular weight of X is A, then molecular weight of Y is -

The hardness of a water sample (in terms of equivalents of CaCO₃) containing 10^–3 M CaSO₄ is (Molar mass of CaSO₄ = 136 g mol^–1)

A metal on combustion in excess air forms X. X upon hydrolysis with water yields H₂O₂ and O₂ along with another product. The metal is :

Poly $$\beta $$ –hydroxybutyrate-co-$$\beta $$-hydroxyvalerate (PHBV) is a copolymer of