The basic structural unit of silicates is

Options

A. `SiO^(-)`
B. `SiO_(4)^(4-)`
C. `SiO_(3)^(2-)`
D. `SiO_(4)^(2-)`

Explanation

To solve the question regarding the basic structural unit of silicates, we can follow these steps:

### Step 1: Understand what silicates are
Silicates are compounds that contain silicon and oxygen, and they are the most abundant class of minerals in the Earth's crust. They are characterized by the presence of the silicate tetrahedron.

**Hint:** Remember that silicates are primarily composed of silicon and oxygen.

### Step 2: Identify the basic structural unit
The basic structural unit of silicates is the silicate tetrahedron, which has the formula SiO4^4-. This tetrahedron consists of one silicon atom (Si) at the center surrounded by four oxygen atoms (O) at the corners.

**Hint:** Focus on the geometric shape of the unit; it is tetrahedral.

### Step 3: Describe the structure of the silicate tetrahedron
In the silicate tetrahedron, the silicon atom is at the center, and the four oxygen atoms are positioned at the vertices of the tetrahedron. Each oxygen atom carries a negative charge, contributing to the overall charge of the tetrahedral unit.

**Hint:** Visualize the tetrahedral shape and the arrangement of the atoms.

### Step 4: Mention the bond angles
The bond angles in a tetrahedral structure are approximately 109.5 degrees. This angle is important as it defines the spatial arrangement of the atoms in the tetrahedron.

**Hint:** Remember the bond angle characteristic of tetrahedral geometry.

### Step 5: Conclude with the answer
The basic structural unit of silicates is the silicate tetrahedron, represented by the formula SiO4^4-.

**Hint:** Reiterate that the answer is a specific chemical formula representing the structural unit.

### Final Answer
The basic structural unit of silicates is SiO4^4-.