Name one compound each in which hydrogen exists in (i) positive oxidation state, and (ii) negative oxidation state.

Explanation

To answer the question, we need to identify one compound where hydrogen has a positive oxidation state and another compound where hydrogen has a negative oxidation state.

### Step-by-Step Solution:

1. **Understanding Oxidation States**:
- The oxidation state of an element in a compound indicates the degree of oxidation (loss of electrons) or reduction (gain of electrons) of that element.
- Hydrogen can exhibit both positive and negative oxidation states depending on the compound it forms.

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