(d)
Some N containing compounds do not give the above set of reaction as in Kjeldahl's method. Sulphur : (w) O.C. + HNO3 → H2SO4 + BaCl2 → (w1) BaSO4
w1
×1× 32 ×100% . 233 where w1 = wt. of BaSO4, w = wt. of organic compound ⇒
(e)
% of S =
Phosphorus : O.C + HNO3 → H3PO4 + [NH3 + magnesia mixture ammonium molybdate] → MgNH4PO4 ∆ Mg2P2O7 →
% of P = (f)
w1
2 × 31 ×100 222 w ×
Carius method : (Halogens) O.C. + HNO3 + AgNO3 → AgX If X is Cl then colour = white If X is Br then colour = dull yellow If X is I then colour = bright yellow
Flourine can't be estimated by this w1 1× (At. wt. of X) ×100 % of X = (M. weight of AgX) × w
9.
EUDIOMETRY : [For reactions involving gaseous reactants and products] The stoichiometric coefficient of a balanced chemical reactions also gives the ratio of volumes in which gasesous reactants are reacting and products are formed at same temperature and pressure. The volume of gases produced is often given by mentioning certain solvent which absorb contain gases. Solvent gas (es) absorb KOH CO2, SO2, Cl2 Ammon Cu2Cl2 CO Turpentine oil O3 Alkaline pyrogallol O2 water NH3, HCl CuSO4 H2 O Check out for certain assumption which are to be used for solving problem related to this.
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