Question

Differentiate between the principle of estimation of nitrogen in an organic compound by 

1. Dumas method 

2. Kjeldahl’s method.

Answer 1

1. Dumas method:

The organic compound is heated strongly with excess of CuO (Cupic Oxide) in an atmosphere of CO₂ where free nitrogen, CO₂ and H₂O are obtained.

2. Kjeldahl’s method:

A known mass of the organic compound is heated strongly with conc. H₂SO₄ , a little amount of potassium sulphate and a little amount of mercury (as catalyst). As a result of reaction, the nitrogen present in the organic compound is converted to ammonium sulphate.