Question
calculate the molecular weight of cellulose acetate if its 0.2%wt/vol solution in acetone(sp. gravity 0.8) shows osmotic rise of 23.1mm against pure acetone at 27C.
Joshi sir comment
By formula πV = nRT
π = hdg, n=w/M
given
0.2%wt/vol solution in acetone means w= 0.2 gm, V = 100 ml= 100/1000 litre = 0.1*10-3 m3 , h = 23.1/1000 m, d = 800 kg/m3 ,
now solve