Consider the given reaction, identify 'X' and 'Y' :

Consider the given reaction, the product A is :

In the sulphur estimation, 0.471 g of an organic compound gave 1.44 g of barium sulphate. The percentage of sulphur in the compound is ____________%. (Nearest integer)

(Atomic Mass of Ba = 137 u)

The equilibrium constant K_c at 298 K for the reaction A + B $$\rightleftharpoons$$ C + D is 100. Starting with an equimolar solution with concentrations of A, B, C and D all equal to 1M, the equilibrium concentration of D is ___________ $$\times$$ 10^$$-$$2 M. (Nearest integer)