1.Oxides are solid and gazieaus substances which include in their compozition two elements .One of them is the oxygen.

SOSO22

Fe3Fe3O4O4

CuCuOO

Na2ONa2O

Al2Al2O3O3

CaOCaO

2. * CO2 : Is found free in the atmosphere, approximate 0,03% in carbonated waters too.

* Al2O3 : Is found in nature in the crystaline form is colorless called Coridon or color with different metalic oxides : Sapphire ( Blue) ; Ruby (red)

• Fe2O3: Is found in nature as iron ore.

FeTiO3FeTiO3 :Are some round particles with diameter of 0,1 and 0,2 mm and is found in magmatic rock or in the river sand .

SiO2 : It`s unequal spread on the earth surface being influenced of the climatic and relief regions and of the petrographic regions construction

MgAl204MgAl204 -Spinel : Is frequently founded in magmatic rokc and metamorphic rock like mottle.

3.Basic oxides (metallic) :

Acid oxides (nemetalic) :

CO2, SO3, P2O5, SiO2

Na2O , Fe2O3, Al2O3,Li2O

* State of matter

* Solid : Fe3O4,Al2O3,CaO,CuO

CaO

Fe3O4

•Gazeous : CO2,SO2,NO2,P2O5,HgO.

CO2CO2

SO2SO2 P2O5P2O5

NO2NO2

* Fluid :H2O

• * White: ZnO• * Black : CuO• * Blue :MnO2• *Yellow: PbO• *Green:Cr2O3

• * H2O : 1g/cm3• * Al2O3 : 3,9 - 4,1g/cm3• * MgO2 : 3,7 - 4,6g/cm3 • * Fe3O4 : 5,25/ cm3

* SO2 - 112g/l

* Fe2O3-Insolubility

* Cao - 1,65 g/l

Solubility

Hardness

Density

-- MgAl2O4 : 7,6 -8MgAl2O4 : 7,6 -8 - CaSiO3 : 4.5 – 5- CaSiO3 : 4.5 – 5 - Al2O3 : 9- Al2O3 : 9 - SiO2 : 7- SiO2 : 7

a.*Basic oxides react with water forming bases.

* Acid oxides react with water forming acids.

* Basic oxides react with acids forming : water + salt

*Acid oxides react with bases forming salt + water .

b.CaO+2HClCaCl2+H2O

CaO+H2OCa(OH)2

CaO+CO2CaCO3

CO2+H2OH2CO3

CO2+2NaOHNa2CO3+H2O

c. Inferior oxides react with oxygen forming superior oxides .

Eg : 2SO + O2 2SO2

2NO + O2 2NO2

2CO + O2 CaCO3

d. Some acid oxides react with basic oxides forming salt

Eg : CaO + CO2 CaCO3

NaO + SO2 NaSO3

MgO + CO2 MgCO3

CaO - Calcium Oxide Line

* Is used in the industry of buiding to prepare material for plaster, like gyps , or to white wasted the walls ; in the chemical industry is used to improve the acid varieties .

SiO2 Silica Dioxide – sand

* Is used in industry of buildings to prepare material for plaster.

ZnO Zinc oxide - white of zinc

* Is mainly used like a white colour in the plastic industry ;paper ; but is also used in pharmace utical industry and cosmeties industry .

PbO Lead oxide

* Is used to produce protective points.

MgO Magnezium Oxide

* Is used like a refractory material for the oreens in the iron industry to produce iron and steel .

CeO2 – Oxid de CeriuCeO2 – Oxid de Ceriu *Is used like "jeweler`s makeup"

in the walls of the oven with function of self-cleaning.

MgAl2O4 –Oxid de Magneziu si AluminiuMgAl2O4 –Oxid de Magneziu si Aluminiu*Are very searched like gems, but unfortunately they are very rare.

V2O5 – Pentaoxidul de VariuV2O5 – Pentaoxidul de Variu*The vanadium oxide is used like Catalyzer to produce sulfuric acid.