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Aromatic amines are weaker bases than ammonia and
aliphatic amines. The increase in the electron density of the
benzene nucleus in the ortho and para positions increases its
activity to the substitution reactions.
Primary aromatic amines react with nitric acid to
form diazonous compounds, secondary nitro compounds on
the amino group, tertiary nitro compounds in the n-position
of the benzene nucleus.
Progress

Formation of amines and their salts
In a dry test tube place 0,5-1 g of methylammonium
chloride and 1-2 g sodium hydroxide. The mixture is
thoroughly mixed with a glass rod. The test tube is closed
with a gas-fired tube and fixed in the foot of the tripod.
The reaction mixture is heated on a gas burner:

+
-
[CH 3–NH 3] Cl + NaOH → CH 3–NH 2↑ + NaCl +
-
+
[CH 3–NH 3] Cl + NaOH → CH 3–NH 2↑ + NaCl + H 2O
H 2 O
methylammonium chloride methylamine

To the opening of the test tube, from which the
methylamine is released, a glass rod is moistened with
concentrated hydrochloric acid. The stick is covered with
"fog".
Methylamine (base) interacts with chloride acid to
form solid salt - methylammonium chloride, whose particles
are perceived as fog:

+ -
CH 3–NH 2 +HCl → [CH 3 – NH 3] Cl + -
CH 3–NH 2 + HCl → [CH 3 – NH 3] Cl

Oxidation of aniline