Hydronium ion is

Options

A. `H^(+)`
B. `H_(3)O^(+)`
C. `OH_(2)^(o+)`
D. `overset(o+)(O)H`

Explanation

**Step-by-Step Solution:**

1. **Understanding the Hydronium Ion**: The hydronium ion is a positively charged ion formed when a hydrogen ion (H⁺) combines with a water molecule (H₂O).

2. **Formation of Hydronium Ion**: When an acid donates a proton (H⁺) to water, the water molecule accepts this proton. This reaction can be represented as:
\[ H_2O + H^+ \rightarrow H_3O^+ \]
Here, H₂O (water) acts as a base and accepts the proton, forming H₃O⁺ (hydronium ion).

3. **Identifying the Correct Option**: The options provided are:
- H⁺
- H₃O⁺
- OH₂⁺
- OH⁻

Among these, the hydronium ion is correctly represented by H₃O⁺.

4. **Conclusion**: Therefore, the correct answer is H₃O⁺, which is the hydronium ion.

**Final Answer**: Hydronium ion is H₃O⁺.

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