In this slide you can get about ,what are oxides and how they classify. In this slides I classify the oxides with respect to nature of oxides as well as the oxygen content in it.

1. Oxides are the
binary
compounds of
Oxygen with
other element
or group of
elements.
For Example:
H2O, N2O2, SiO2,
Al2O3, ZnO, CO2
etc.
Oxides:
Fe2O3

2. Classification of Oxides
Depending upon nature and the properties exhibited
by compounds, they are classified into:
Acidic oxides
Basic oxides
Amphoteric oxides
Neutral oxides

3. Acidic Oxides
An acidic oxide is an oxide which when
combined with water gives off an acid.
• SO3 + H2O → H2SO4
• B2O3 + H2O → 2H3BO3
Non-metals react with oxygen to form acidic
compounds of oxides which are held together
by covalent bonds.
Examples: NO, CO2

4. Properties & Preparation Of
Acidic Oxides
C+4HNO3→CO2+4NO2+2H2O
• Acidic Oxides formed acids when reacts with
water.
• They produce salts when reacting with a base.
• They are covalent in nature.
• They work as an oxidizing agent.

5. Basic Oxides
A basic oxide is an oxide which when
combined with water gives off a base
 Na2O + H2O → 2NaOH
Metals react with oxygen to give basic
compounds of oxygen.
These compounds are usually ionic in nature.
Examples: M2O3, MO2, ThO2

6. CaCO3 −Δ→CaO+CO2
• Basic Oxides formed bases when reacts with
water.
• They produce salts when reacting with an
acid.
• They are ionic in nature.
• They work as an oxidizing agent.
Properties & Preparation Of Basic
Oxides

7. Amphoteric Oxides
Amphoteric oxides are compounds of oxygen
which exhibits both acidic as well as basic
characteristics.
• Acidic characteristics:
AL2O3 + 6HCl → AlCl 3+ 3H2O
• Basic characteristics:
Al2O3 +2OH– + 3H2O → 2[Al (OH)4]–

8. ZnCO3___________
>ZnO+CO3
• They exhibits both acidic as well as basic
characteristics.
• These oxides when reacting with acid
undergoes a neutralization reaction to form
water and salt.
• Similarly reacts with the alkali to form salt
and water.
Properties & Preparation Of
Amphoteric Oxides

9. Some compounds react with oxygen to form
oxides which do not exhibit acidic nor basic
characteristics. Such compounds are called as
neutral compounds of oxygen.
Example: NO, CO.
Neutral Oxides

10. Properties & Preparation Of Neutral
Oxides
8 HNO3 + 3Cu →3Cu(NO3)2 + 3H2O + 2 NO
• They shows neither basic nor acidic properties.
• They are neutral toward litmus.
• Under certain condition some neutral oxides do
react with acids and bases.

11. Classification of Oxides
They are further classified
into:
 Acidic Oxides
 Basic Oxides
 Amphoteric Oxides
 Neutral Oxides
They are further classified
into:
 Peroxides
 Superoxides
 Dioxides
 Sub Oxides
 Compound Oxides
Depending upon the oxygen content in the compound ,these
oxides are classified into:
Normal Oxides: Polyoxides:

12. Normal Oxides:
“It is that oxide of oxygen in which the oxidation state of
oxygen is normal i.e. -2”
For Example:
• SO2
• CO2
• CaO
• AL2O3

13. 4Li+O2→2Li2O
S+O →SO2
2Ca+O2 →2CaO
• It can be acidic
• It can be basic
• It can be amphoteric
• It can be neutral
Properties & Preparation Of
Normal Oxides

14. It is that oxide of oxygen in which the oxidation
state of oxygen is not normal i.e. -2
• it contains O-O bond
They are further divided into:
• Peroxide
• Superoxides
• Dioxides
• Sub oxides
• Compound oxides
PolyOxides:

15. “ They are those poly oxides in which the
oxidation state of Oxygen is -1”
For Example: Na2O2
Structure: Na + O-
O- Na +
Preparation:
4 Na + O2 → 2 Na2O.
2 Na2O + O2 → 2 Na2O2
PerOxides (-1) :

16. • They have more proportion of Oxygen than
normal oxide.
• They contain peroxide (O-O)-2 bond.
• On reacting with water or dilute acid they
produce H2O2.
Na2O2+2H2O →H2O2+2NaOH
Properties Of PerOxides (-1) :

17. “ They are those poly oxides in which the
oxidation state of Oxygen is -1/2”
For Example: KO2
Preparation:
K + O2 → KO2
SuperOxides (-1/2) :

18. • They are ionic in nature.
• They contain superoxide (O-O)-1 bond.
• They don’t produce H2O2 with acids ,only with
water.
KO2+H2O →H2O2+KOH
Properties Of SuperOxides (-1/2) :

19. “These are those oxides which contain two
oxygen atoms in it in such a way that each
oxygen is directly attached to the central
atom”.
For Example: MnO2 , PbO2
Structure:
O=Mn=O , O=Pb=O
Dioxides :

20. Properties & Preparation Of
Dioxides :
Mn+O2 →MnO2
•They have more proportion of oxygen.
•They are used as an oxidizing agent.
•They are most common oxides.
•They are relatively stable oxides.

21. “These are the oxides that containing the
lowest or an unusually small proportion of
oxygen.”
For Example: Na2O
Preparation:
2 NaOH + 2 Na → 2 Na2O + H2
Suboxides :

22. • They have the normal oxidation state of
Oxygen.
• Suboxides typically feature extensive bonding
between the electropositive element.
• They often leads to cluster.
Properties Of Suboxides :

23. “Compound oxides are metallic oxides that
behave as if they are made up of two oxides,
one that has a lower oxidation and one with a
higher oxidation of the same metal.”
For Example:
• Red lead: Pb3O4=PbO2+2PbO
• Ferro-ferric oxide: Fe3O4=Fe2O3+FeO
Compound Oxides :

24. Fe2+ + 2Fe3+ + 8OH- →Fe3O4 + 4H2O
• On treatment with an acid, compound oxides
give a mixture of salts.
Fe3O4 +8HCl→2FeCl3 +FeCl2+4H2O
Properties & Preparation Of
Compound Oxides :