Which one of the oxides is neutral?

Options

A. CO
B. `SnO_4`
C. `ZnO`
D. `SiO_2`

Explanation

To determine which oxide is neutral among the given options, we need to analyze the nature of each oxide mentioned: carbon monoxide (CO), zinc oxide (ZnO), silicon dioxide (SiO2), and tin(IV) oxide (SnO2).

### Step-by-Step Solution:

1. **Identify the Oxides**: The oxides we are considering are:
- Carbon monoxide (CO)
- Zinc oxide (ZnO)
- Silicon dioxide (SiO2)
- Tin(IV) oxide (SnO2)

2. **Classify Each Oxide**:
- **Carbon monoxide (CO)**: CO is known to be a neutral oxide. It does not exhibit acidic or basic properties in reactions.
- **Zinc oxide (ZnO)**: ZnO is classified as an amphoteric oxide. This means it can react with both acids and bases, showing both acidic and basic properties.
- **Silicon dioxide (SiO2)**: SiO2 is typically considered an acidic oxide. It reacts with bases but not with acids.
- **Tin(IV) oxide (SnO2)**: SnO2 is also an amphoteric oxide, meaning it can react with both acids and bases.

3. **Conclusion**: Among the oxides listed, carbon monoxide (CO) is the only oxide that is neutral.

### Final Answer:
The neutral oxide among the given options is **carbon monoxide (CO)**.

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