Which one of the following oxides has highest acidic character ?

Options

A. `CO_(2)`
B. `Cl_(2)O_(7)`
C. `SiO_(2)`
D. `SO_(2)`

Answer

To determine which oxide has the highest acidic character among the given options, we will analyze the oxidation states of the central atoms in each oxide. The acidic character of an oxide generally increases with the oxidation state of the central atom.

### Step-by-Step Solution:

1. **Identify the Oxides**: The options provided are:
- CO2 (Carbon Dioxide)
- Cl2O7 (Dichlorine Heptoxide)
- SiO2 (Silicon Dioxide)
- SO2 (Sulfur Dioxide)

2. **Calculate the Oxidation State of Each Central Atom**:
- **For CO2**:
- Oxygen has an oxidation state of -2.
- There are 2 oxygen atoms, contributing a total of -4.
- Let the oxidation state of carbon be \( x \).
- The equation becomes: \( x + (-4) = 0 \) → \( x = +4 \).
- Thus, the oxidation state of carbon in CO2 is +4.

- **For Cl2O7**:
- Oxygen has an oxidation state of -2.
- There are 7 oxygen atoms, contributing a total of -14.
- Let the oxidation state of chlorine be \( y \).
- The equation becomes: \( 2y + (-14) = 0 \) → \( 2y = +14 \) → \( y = +7 \).
- Thus, the oxidation state of chlorine in Cl2O7 is +7.

- **For SiO2**:
- Oxygen has an oxidation state of -2.
- There are 2 oxygen atoms, contributing a total of -4.
- Let the oxidation state of silicon be \( z \).
- The equation becomes: \( z + (-4) = 0 \) → \( z = +4 \).
- Thus, the oxidation state of silicon in SiO2 is +4.

- **For SO2**:
- Oxygen has an oxidation state of -2.
- There are 2 oxygen atoms, contributing a total of -4.
- Let the oxidation state of sulfur be \( w \).
- The equation becomes: \( w + (-4) = 0 \) → \( w = +4 \).
- Thus, the oxidation state of sulfur in SO2 is +4.

3. **Compare the Oxidation States**:
- CO2: +4
- Cl2O7: +7
- SiO2: +4
- SO2: +4

4. **Determine the Highest Acidic Character**:
- The oxide with the highest oxidation state is Cl2O7, which has an oxidation state of +7. Higher oxidation states generally correlate with greater acidic character.

5. **Conclusion**:
- Therefore, the oxide with the highest acidic character among the given options is **Cl2O7**.

### Final Answer:
**Cl2O7**