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Рb + H 2О = РbО + Н 2↑.

Interaction of metals with alkalis

Be, Al, Ga, Sn, Pb, Zn interact with alkali forming hydroxo complexes.

Zn + 2NaОН + 2H 2O = Na 2[Zn(OН) 4] + H 2,

2Al + 2KОН + 6H 2O = 2K[Al(OН) 4] + 3H 2.

Interaction of metals with acids

Almost all metals are oxidized by acids. The nature of the interaction with

acids depends on the metal activity, as well as on the acid and its concentration.

Hydrochloric acid HCl, regardless of concentration, interacts with metals located

in the range of activity up to Hydrogen. In this case chlorides are formed and

hydrogen is released:
Fe + 2HСl (con) = FeCl 2 + Н 2,

Сu + HСl (con) ≠.
Diluted sulfuric acid H2SO4 interacts only with those metals that are in the

range of activity up to Hydrogen. .
2Al + 3H 2SO 4(s) = Al 2(SO 4) 3 + 3Н 2,

Ag + H 2SO 4(s) ≠.

Concentrated sulfuric acid oxidizes metals up to Silver inclusive, and the oxidizing
+6
is agent S . Passive metals, as a rule, restore H 2SO 4 to SO 2, active metals - to S

or H 2S, depending on the concentration of acid and the temperature.

o
t
2Ag + 2Н 2SO 4(c)  Ag 2SO 4 + SO 2 + 2Н 2О
4Mg + 5H 2SO 4(c) = 4MgSO 4 + H 2S + 4H 2O

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