S.L. 437.63 Art. 3CuSO 4 ml of ethanol, = 40 g/100 ml ignited.

Reagents 3.1 Potassium sulfate.

3.2 Catalyst: copper (II) oxide CuO or copper (II) sulfate pentahydrate,

ꞏ 5H O 2 3.3 Granulated zinc. ρ 3.4. Sulfuric acid, = 1,84 g/ml. 20 3.5 Sulfuric acid c(½H SO ) = 0,5 mol/l. 2 4 3.6 Sulfuric acid c(½H SO ) = 0,1 mol/l. 2 4 3.7 Methyl red indicator; dissolve 300 mg of methyl red in 100 σ 95-96% (v/v) ß 3.8 Sodium hydroxide solution (Technical grade may be used) (m/v: 40%). 3.9 Sodium hydroxide solution c = 0,25 ml/l 3.10 Sodium hydroxide solution c = 0,1 mol/l.

3.11 Granulated pumice stone, washed in hydrochloric acid and 3.12 Acetanilide (m.p. = 114ºC, N = 10,36%) 3.13 Sucrose (nitrogen free).