Pyrosilicate ion is

Options

A. `SiO_(2)^(2-)`
B. `SiO_(4)^(2-)`
C. `Si_(2)O_(6)^(7-)`
D. `Si_(2)O_(7)^(6-)`

Explanation

To determine the correct answer for the question regarding the pyrosilicate ion, we will analyze the options provided and understand the structure of the pyrosilicate ion.

### Step-by-Step Solution:

1. **Understanding the term "pyrosilicate":**
- Pyrosilicate refers to a specific type of silicate ion that is formed by the combination of two silicate tetrahedra.

2. **Identifying the options:**
- The options given are:
- A) SiO2-
- B) SiO4-
- C) Si2O7-
- D) Si2O76-

3. **Analyzing the structure of pyrosilicate:**
- A pyrosilicate ion is typically represented by the formula Si2O7^6-. This indicates that it consists of two silicon atoms and seven oxygen atoms, with a total of six negative charges.

4. **Understanding the tetrahedral units:**
- The pyrosilicate ion is made up of two silicate tetrahedra (SiO4^4-), which share one oxygen atom. This sharing of oxygen leads to the formation of the pyrosilicate structure.

5. **Conclusion:**
- Based on the analysis, the correct answer to the question is **Si2O76-**, which corresponds to option D.

### Final Answer:
The pyrosilicate ion is **Si2O76-** (Option D).

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