Which of the following is correct structur of anion of pyrosilicates ?

Options

A.
B.
C.
D.

Answer

To determine the correct structure of the anion of pyrosilicates, we need to analyze the options based on the known formula and characteristics of pyrosilicates.

### Step-by-Step Solution:

1. **Understanding Pyrosilicates**:
- The formula for pyrosilicates is \( \text{Si}_2\text{O}_7^{6-} \). This means that in the structure, there are two silicon atoms and seven oxygen atoms.

2. **Analyzing the Structure**:
- In pyrosilicates, one oxygen atom is shared between two silicon atoms. This sharing is crucial for identifying the correct structure.

3. **Evaluating the Options**:
- **Option A**: Contains one silicon atom and four oxygen atoms. This corresponds to \( \text{SiO}_4^{4-} \), which does not match the pyrosilicate formula.
- **Option B**: Contains two silicon atoms and seven oxygen atoms. This corresponds to \( \text{Si}_2\text{O}_7^{6-} \) and has the correct charge of -6. This option correctly represents the structure of pyrosilicates.
- **Option C**: Contains two silicon atoms but shows two oxygen atoms shared between them. This does not represent a pyrosilicate structure.
- **Option D**: Similar to option C, it shows a structure where two oxygen atoms are shared, indicating a different type of silicate, not a pyrosilicate.

4. **Conclusion**:
- Based on the analysis, **Option B** is the correct structure of the anion of pyrosilicates, as it accurately reflects the formula \( \text{Si}_2\text{O}_7^{6-} \) with the appropriate sharing of oxygen atoms.

### Final Answer:
The correct structure of the anion of pyrosilicates is represented by **Option B**.