Enter the oxidation number of one atom of each element in each reactant and product

Question

Enter the oxidation number of one atom of each element in each reactant and product

CH₄(g)+2 O₂(g)---->CO₂(g)+2 H₂ O(g)

1. C in CH₄
2. H in CH₄
3. O in O₂
4. C in CO₂
5. O in CO₂
6. H in H₂O
7. O in H₂O

Answer 1

CH₄(g) + 2 O₂(g)---->CO₂(g) + 2 H₂ O(g)

In determining oxidation number all polar bonds are treated as if they're ionic with the bonding electron pair belonging to the more electronegative atom.

All C–H bonds count as C^– and H^+, all C–O bonds count as C⁺ and O^–, etc.

Electrons count as equally shared only in nonpolar bonds

So O–O bonds count as O⋅ and ⋅O

1. C in CH₄ oxidation number = –4
2. H in CH₄ oxidation number = +1
3. O in O₂ oxidation number = 0
4. C in CO₂ oxidation number = +4
5. O in CO₂ oxidation number = –2
6. H in H₂O oxidation number = +1
7. O in H₂O oxidation number = –2