An element forms a molecule by sharing or donating/accepting electrons.
as shown under
The valency and therefore the oxidation state is expected to be 4 or -4 as it would donate or accept 4 electrons to attain stability.
The oxidation state is therefore variable in carbon from -4 to +4
Concider a compound like CO2
oxygen has -2 oxidation state,
the sum of oxidation state of carbon and oxygen is zero since the molecule is neutral.
-2 x 2 + carbon oxidation state=0
oxidation state of carbon = +4
Similarly for a compound like CH4,
the oxidation state would be
+1 x 4 + oxidation state of carbon = 0
oxidation state of carbon = -4
Now consider another reaction where in oxidation number of carbon undergoes change and has variable oxidation state CH2=CH2 + H2O CH3-CH2OH
oxidation states of carbon in ethene: -2 , -2 ; and in ethanol they are : -3 -1
The oxygen has -2 oxidation state.
The oxidation state of carbon is therefore found out as under
-2 + oxidation state of carbon = 0
oxidation state = -2
Let us consider a molecule of CF4.
The fluorine has -1 oxidation state.
The oxidation state of carbon is therefore found out as under
-1x 4 + oxidation state of carbon = 0
oxidation state=+4
Let us consider a molecule of CH3Cl.
The chlorine has -1 oxidation state. The hydrogen has +1 oxidation state.
The oxidation state of carbon is therefore found out as under
-1 + 1 x 3 + oxidation state of carbon = 0
oxidation state= +2
If it is sharing, it is covalent bond, if it is by donating/accepting electrons, it is an ionic bond.
The degree of oxidation of an element in a molecule is called oxidation state.This is particularly significant where an element can exhibit variable valency.
Oxidation states of free atoms are zero.
The oxidation state of free ion is the charge carried by it.
The sum of all oxidation states in a neutral molecule is zero.
The oxidation states of hydrogen is +1 and oxygen -2 with a few exceptions.
The degree of oxidation of an element in a molecule is called oxidation state.This is particularly significant where an element can exhibit variable valency.
Oxidation states of free atoms are zero.
The oxidation state of free ion is the charge carried by it.
The sum of all oxidation states in a neutral molecule is zero.
The oxidation states of hydrogen is +1 and oxygen -2 with a few exceptions.
Introduction :
Carbon has configuration 2s2 2p2as shown under
The valency and therefore the oxidation state is expected to be 4 or -4 as it would donate or accept 4 electrons to attain stability.
The oxidation state is therefore variable in carbon from -4 to +4
Concider a compound like CO2
oxygen has -2 oxidation state,
the sum of oxidation state of carbon and oxygen is zero since the molecule is neutral.
-2 x 2 + carbon oxidation state=0
oxidation state of carbon = +4
Similarly for a compound like CH4,
the oxidation state would be
+1 x 4 + oxidation state of carbon = 0
oxidation state of carbon = -4
Now consider another reaction where in oxidation number of carbon undergoes change and has variable oxidation state CH2=CH2 + H2O CH3-CH2OH
oxidation states of carbon in ethene: -2 , -2 ; and in ethanol they are : -3 -1
Other Compounds.
Let us consider a molecule of CO.The oxygen has -2 oxidation state.
The oxidation state of carbon is therefore found out as under
-2 + oxidation state of carbon = 0
oxidation state = -2
Let us consider a molecule of CF4.
The fluorine has -1 oxidation state.
The oxidation state of carbon is therefore found out as under
-1x 4 + oxidation state of carbon = 0
oxidation state=+4
Let us consider a molecule of CH3Cl.
The chlorine has -1 oxidation state. The hydrogen has +1 oxidation state.
The oxidation state of carbon is therefore found out as under
-1 + 1 x 3 + oxidation state of carbon = 0
oxidation state= +2
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