Ammonium carbonate when heated to 200°C gives a mixture of NH3( g),CO2( g) ,  and H2O-vapour with a density of 13.0. The degree of dissociation of ammonium carbonate is

NH42CO3( g)⇌⟶  200°C2NH3( g)+CO2( g)+H2O(g)Vapour density of Ammonium carboante   (D) = Mol. mass of NH42CO32=962=48Vapour density of the mixture (d) =13n(no. of moles of gaseous products from 1 mole of reactant) =4Degree of dissociation,x=D-dd(y-1) =48-1313(4-1) =3513×3 =0.89