Determine the oxidation number (oxidation state) of each element in CH 4. C : H : Determine the oxidation number (oxidation state) of each element in SO 2. S : O : Determine the oxidation number (oxidation state) of each element in BF 3. B : F :

1. In CH₄ molecule:

The oxidation number of H = ( + 1)

The oxidation number of C = ( - 4)

2. In SO₂ molecule:

The oxidation number of O = ( - 2)

the oxidation number of S = ( + 4)

3. In BF₃ molecule:

The oxidation number of F = ( - 1)

the oxidation number of B = ( + 3)

Explanation:

Oxidation number represents the oxidation state of an element in a given chemical compound, which can be zero, negative or positive.

The overall charge on a given chemical molecule is equal to sum of the oxidation numbers of all the elements in that molecule.

Now, calculating the oxidation number-

1. In CH₄ molecule:

As we know, the oxidation number of H = ( + 1)

and the overall charge on the molecule = 0

Let the oxidation number of C be x

∴ x + ( + 1) * 4 = 0

⇒ x = ( - 4)

Therefore, the oxidation number of C = ( - 4)

2. In SO₂ molecule:

As we know, the oxidation number of O = ( - 2)

and the overall charge on the molecule = 0

Let the oxidation number of S be x

∴ x + ( - 2) * 2 = 0

⇒ x = ( + 4)

Therefore, the oxidation number of S = ( + 4)

3. In BF₃ molecule:

As we know, the oxidation number of F = ( - 1)

and the overall charge on the molecule = 0

Let the oxidation number of B be x

∴ x + ( - 1) * 3 = 0

⇒ x = ( + 3)

Therefore, the oxidation number of B = ( + 3)