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replaced. With alcohols form esters, under the action of
water-absorbing substances - anhydrides, under the action of
ammonia - ammonium salts, which, when heated, are
converted into amides.

Progress

The reaction of the "silver" mirror - a characteristic
reaction to the aldehydes.
Aldehydes are easily oxidized when they interact with
an ammoniacal solution of an oxide argentum to form the
corresponding acids and metal argentum, which precipitates
on the glass surface in the form of a "silver mirror":

O O

CH C + 2[Ag(NH) ]OH CH C +2Ag + 4NH + 2HO
2
3
3 3 2 3
H OH

етанова кислота
In a clean tube, washed in turn with 10% alkaline
3
solution and distilled water, pour 3-4 cm of 1% solution of
nitrate argentum and add 5% ammonia solution in such a
quantity as to make the precipitate formed first dissolve
first. To the resulting ammonia solution [Ag (NH 3) 2] OH, 1
3
cm of 1% solution of aldehyde (methanal or ethanal) is
added and the mixture is carefully heated.
The reduction reaction of the aldehydes with cuprum
(II) hydroxide
3
In a test-tube pour 0,5 cm of 10 % solution of
3
methanal or manalu, 3-4 cm of 10% sodium hydroxide and
added drops of 5% solution of cuprum (II) sulfate. Heat the
contents of the vial.