During estimation of nitrogen present in an organic compound by Kjeldhal's method, the ammonia evolved from 0.5 g of the compound neutralized 10 mL of 1 M H_(2)SO_(4). Find the percentage of nitrogen in the compound.

During estimation of nitrogen present in an organic compound by Kjeldh

1.	During estimation of nitrogen present in an organic compound by Kjeldhal's method, the ammonia evolved from 0.5 g of the compound neutralized 10 mL of 1 M H_(2)SO_(4). Find the percentage of nitrogen in the compound.
Answer» SOLUTION :Volume of `H_(2)SO_(4)` used = 10 mL of `1 M H_(2)SO_(4)` Now`H_(2)SO_(4) + 2NH_(3) rarr (NH_(4))_(2)SO_(4)` Now 1 mole of `H_(2)SO_(4)` reacts with 2 moles of `NH_(3)`. `:.` 1- mL of `1M H_(2)SO_(4) -= 20 mL` of `1 M NH_(3)` Now 1000 mL of `1 M NH_(3)` contains `N = 14 g :. 20 mL` of `1 M NH_(3)` will contain `N =(14)/(1000) xx 20` But this amount of nitrogen is present in 0.5 g of the organic compound. `:.` Percentage of nitrogen `= (14 xx 20)/(1000) xx (100)/(0.5) = 56.0`. Alternatively, % age of `N = (1.4 xx "Vol. of acid used" xx "BASICITY of acid" xx "Molarity of acid")/("Mass of the SUBSTANCE taken") = (1.4 xx 10 xx 2 xx 1)/(0.5) = 56.0`