Given the following chemical equation:
H₂(g) + F₂(g) --> 2HF(g)
A few observations were made:
Hydrogen always has an oxidation number of 1. so it has an
oxidation number of 1 in H₂ and HCI.
• Fluorine is in Group 7 or 17, therefore it must have an oxidation
number of -1 both as F₂ and HF.