The ammonia evolved from 2g of a compound in Kjeldahl's estimation of nitrogen neutralizes 10 mL of 2 M H2SO4 solution. The weight percentage of nitrogen in the compound is
28
2NH2+H2SO4 −→(NH4)2SO4
10ml
2ml
millimole of H2SO4=mmol of NH32=20
Mmol NH3=mmol of N=40
=40×141000=5601000=0.56g
Wn
% of N=0.562×100=28