`25 cm^(3)` of ferrous ammonium sulphate solution require `20 cm^(3)` of 0.1 N potassium dichromate solution. Calculate the amount of ferrous ammonium sulphate crystals dissolved in `250 cm^(3)` of the solution. (Given equivalent).

Explanation

`underset("FAS")(N_(1)V_(1)) = underset("K_(2)Cr_(2)O_(7))(N_(2)V_(2)) rArr N_(1) = (N_(2)V_(2))/V_(1) = (0.1 xx 20)/25 = 0.08`
Equivalent mass of ferrous ammonium sulphate crystals = 278.
`("mass")/(250 ml) = (N xx g. "eq. mass")/4 = (0.08 xx 278)/4 = 5.56`g