I uploaded the answer to a file hosting. Here's link:
tinyurl.com/wtjfavyw
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<h3>What is the oxidation number of oxygen in H2O?</h3>
Oxygen almost always has an oxidation number of -2, except in peroxides (H 2 O 2) where it is -1 and in compounds with fluorine (OF 2) where it is +2. Hydrogen has an oxidation number of +1 when combined with non-metals, but it has an oxidation number of -1 when combined with metals.
<h3><em>Sure hoep this helps you :)</em></h3>