Question

Estimate the density of a 55%(v/v) nitric acid

Answer 1

Basis : 100 ml of solution

Volume of nitric acid = 55 ml

Volume of water = 100-55= 45 ml

Density of water = 1000 Kg/m3 = 1 g/ml

Density of nitric acid = 1510 Kg/m3 1.51 g/ ml

Mass of water = 45 ml =45 grams

Mols of water = 45/18=2.5 mol

Mass of nitric acid =55*1.51=83.05 grams

Mols of nitric acid =83.05/63=1.318 mols

Mol fraction of water = 2.5/(2.5+1.318) =0.65

Mol fraction of nitric acid =1-0.65=0.35

Density of mixture =(mol fraction nitric acid *density of nitirc acid) + ( mol fraction water * density of water ) = .35*1.51 +0.65*1 = 1.1785 g/ml = 1178.5 Kg/m3