The normality of orthophosphoric acid having purity of 70% by weight and specific gravity 1.54 is :

Options

A. 11N
B. 22N
C. 33N
D. 44N

Answer

C

Explanation

Equivalent weight of orthophosphoric acid `(H_3PO_4)`
`=(3+31+64)/3 = 98/3`
Now 100 g solution contains 70 g `H_3PO_4`
`100/(1000 xx1.54)` litre of solution contains `70/(98//3) g`
equivalent of `H_3PO_4`
Normality of solution
`=((70 xx3)/98)/(1/(10xx1.54))=(70xx3)/98xx10xx1.54 =33N`