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3. Interaction with one another forming salt (usually an element with lower

oxidation is recorded as salt cation, and metal with a higher oxidation state – as

anion):

 2  3  2
ZnO + Al 2 O 3 = Zn (AlO 2) 2

(Al 2O 3 + H 2O → 2HАlO 2 ).

3.2 Bases

Bases are complex compounds that consist of metal atoms and hydroxyl

groups.

The number of hydroxyl groups indicates the acidity of the base and is

determined by the oxidation state of a metal.

According to the theory of electrolytic dissociation the bases are called

electrolytes, and during their dissociation only hydroxide ions are formed in the

form of anions.

The bases are classified:

- according to solubility they are soluble (alkali) and insoluble;

- according to the number of hydroxyl groups per one acid they are two-acid

and multi-acid.

Nomenclature of the Foundations

The names of the bases are formed as follows:

Name of the element in the nominal case + (degree state) + hydroxyd

The number of hydroxyl groups coincides with the valence (the oxidation state)

of a metal. NaOH - sodium hydroxide, Mn(OH) 2 - manganese (II) hydroxide,

Mn(OH) 3 - manganese (III) hydroxide

Chemical properties of the bases

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