The major product of the above reactions is :

A polysaccharide 'X' on boiling with dil H₂SO₄ at 393 K under 2-3 atm pressure yields 'Y'. 'Y' on treatment with bromine water gives gluconic acid. 'X' contains $$\beta$$-glycosidic linkages only. Compound 'X' is :

During the qualitative analysis of salt with cation y²⁺, addition of a reagent (X) to alkaline solution of the salt gives a bright red precipitate. The reagent (X) and the cation (y²⁺) present respectively are :

2O₃(g) $$\rightleftharpoons$$ 3O₂(g)

At 300 K, ozone is fifty percent dissociated. The standard free energy change at this temperature and 1 atm pressure is ($$-$$) ____________ J mol^$$-$$1. (Nearest integer)

[Given : ln 1.35 = 0.3 and R = 8.3 J K^$$-$$1 mol^$$-$$1]