The basic structural unit in silicates is

Options

A. `Si_(2)O_(6)^(4-)`
B. `SiO_(3)^(2-)`
C. `SiO_(4)^(4-)`
D. `Si_(2)O_(7)^(6-)`

Answer

To determine the basic structural unit in silicates, we can follow these steps:

### Step 1: Identify the Composition of Silicates
Silicates are compounds that primarily contain silicon and oxygen. The basic structural unit in silicates is derived from the combination of these two elements.

**Hint:** Think about the common elements found in silicates and their typical bonding patterns.

### Step 2: Determine the Basic Unit
The basic unit in silicates is the silicate ion, which is represented as SiO4^4-. This ion consists of one silicon atom surrounded by four oxygen atoms.

**Hint:** Recall the formula for the silicate ion and how many oxygen atoms surround the silicon atom.

### Step 3: Understand the Structure
In the SiO4^4- unit, the silicon atom is at the center, and the four oxygen atoms are positioned at the corners of a tetrahedron. This arrangement gives the silicate ion its characteristic tetrahedral geometry.

**Hint:** Visualize the tetrahedral shape and how the atoms are arranged in three-dimensional space.

### Step 4: Consider Hybridization
The silicon atom in the SiO4^4- unit undergoes sp3 hybridization, which allows it to form four equivalent covalent bonds with the oxygen atoms. This hybridization is essential for the formation of the tetrahedral structure.

**Hint:** Remember the concept of hybridization and how it relates to the geometry of molecules.

### Conclusion
The basic structural unit in silicates is SiO4^4-, which has a tetrahedral shape and involves sp3 hybridization of the silicon atom.

**Final Answer:** SiO4^4-

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