Differentiate between the principle of estimation of nitrogen in an organic compound by (i) Dumas method and (ii) Kjeldahl's method

Differentiate between the principle of estimation of nitrogen in an or

1.	Differentiate between the principle of estimation of nitrogen in an organic compound by (i) Dumas method and (ii) Kjeldahl's method
Answer» Solution :(i) In Dumas method, a KNOWN mass of the organic COMPOUND is heated with EXCESS of CuO is an atmosphere of `CO_(2)`, when nitrogen of the organic compound is concerted in to `N_(2)` gas. On the base of volume of `N_(2)`, the % of N calculated. (ii) In Kjeldahl.s method, a known mass of the organic substance is heated with concentrate `H_(2)SO_(4)` in presence of `K_(2)SO_(4)` and little `CuSO_(4)` or Hg catalyst when nitrogen is concerted into ammonium sulphate and then it is boiled with excess of NaOH solution and to LIBERATE `NH_(3)`, the % of N is calculated