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35. SUBGROUP OF OXYGEN.

The subgroup of oxygen includes элементы:кислород, sulfur, selenium, tellurium, polonium.


Properties of elements VI-A of subgroup.
Element Oxygen
O		 Sulfur
S		 Selenium
Se		 Tellurium
Te		 Polonium
Po
Property
Order number of element 8 160,05 34 52 84
Relative atomic mass 15,999 32,067 78,96 127,60 208,982
Temperature of melting, C0 - 219 119 217 450 254
Temperature of boiling, C0 - 183 445 685 1390 962
G/cm3 density 1,27
(firm)
 2,1 4,8 6,2 9,4
Oxidation levels - 2 (with fluorine +2, in peroxides-1) - 2, +4, +6 - 2, +4, +6 - 2, +4, +6 - 2, +4, +6

Allotropy of oxygen and sulfur.

Oxygen has two allotropic modifications: kislorodo2 and O3 ozone. Oxygen turns into ozone when passing electric discharge through it, for example lightning discharge:

3O2 2O3s

Ozone more active in comparison with oxygen, due to instability of substance and education at decomposition of elemental oxygen

O3O2 s+ ABOUT

At sulfur it is possible to allocate two versions: crystal

сера


and plastic

сера

Transition from crystal to plastic happens when heating to boiling temperature at the subsequent rapid cooling.

Receiving oxygen and sulfur.

oxygen sulfur

1. Decomposition of potassium permanganate when heating:
2KMnO4 = K2MnO4 + MnO2 + O2
2. Hydrogen peroxide decomposition:
2H2O2 = 2H2O + O2
3. Potassium nitrate decomposition:
2NaNO3 =2NaNO2 + O2
4. Potassium chloride decomposition:
2KClO3 = 2KCl + 3O2
4. From air.

 

 1. Smelting from breed.
2. Partial oxidation of hydrogen sulfide:
2H2S + O2=2H2O + 2S
3. Sodium thiosulphate acidulation:
Na2S2O3 + 2HCl = 2NaCl + SO2 + H2O + S

Chemical properties of oxygen and sulfur

oxygen sulfur
1. Interaction with metals:
2Cu + O2 = 2CuO
2. Burning of nonmetals:
S+O2 = SO2s
3. Burning of complex substances:
2H2S + 3O2 = 2H2O + 2SO2s		 1. Sulfur burning:
2H2S + 3O2 = 2H2O + 2SO2s
2. Interaction with nonmetals:
H2 + S = H2Ss
S+O2 = SO2s
3. Oxidation by sulphuric acid:
S + 2H2SO4 = 2H2O + 3SO2s
4. Interaction with alkalis when heating:
S + 2H2SO4 = 2H2O + 3SO2s

Use of oxygen and sulfur

oxygen sulfur
Welding and cutting of metals. metallurgical production, in respiratory devices, oxidizer of rocket fuel, etc. Receiving carbon sulfur, sulphuric acid, rubber curing, treatment of skin diseases, protection of plants against mealy dew

Information on others chemical to the elementakh:selena. tellurium and Polonius.

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