Paragraph 4 REAGENTS

4.1

Hydrogen peroxide solution (H₂O₂ ρ = 1.11 g/ml) 30%.

Sodium hydroxide solution, about 2 M

4.2

Dissolve 8 g of sodium hydroxide in pellet form in 100 ml of water.

Diluted hydrochloric acid solution, about 6 M

4.3

Mix one volume of hydrochloric acid (ρ = 1.18 g/ml) with 1 volume of water.

4.4

Acetic acid (99.7% CH₃COOH) (ρ = 1.05 g/ml)

Acetic acid solution (1:2), about 6 M

4.5

Mix one volume of acetic acid (4.4) with 2 volumes of water.

4.6

Solution of 1-nitroso-2-naphthol in 100 ml of acetic acid (4.4). Add 100 ml of lukewarm water. Mix thoroughly. Filter at once. The solution obtained must be used immediately.