Basic unit fo zeolite, mica, asbestos and feldpar is

Options

A. 1. `(--overset(R)overset(|)underset(R)underset(|)Si-O--)_(n)(R=Me)`
B. 2. `(SiO_(3))^(2-)`
C. 3. `(SiO_(4))^(4-)`
D. 4. `SiO_(2)`

Explanation

To determine the basic unit for zeolite, mica, asbestos, and feldspar, we will analyze the chemical composition of each of these minerals step by step.

### Step 1: Identify the Composition of Each Mineral
1. **Zeolite**: The chemical composition of zeolite is hydrated aluminum silicate. This means it contains aluminum (Al), silicon (Si), oxygen (O), and water (H2O).

2. **Mica**: Mica is composed of potassium aluminum silicate. It contains potassium (K), aluminum (Al), silicon (Si), and oxygen (O).

3. **Asbestos**: Asbestos is known as hydrous magnesium silicate. It consists of magnesium (Mg), silicon (Si), oxygen (O), and water (H2O).

4. **Feldspar**: Feldspar is chemically known as potassium silicate. It contains potassium (K), silicon (Si), and oxygen (O).

### Step 2: Identify the Common Element
Now, we will look for a common element in the compositions of these minerals.
- All four minerals contain **silicate** as a fundamental component.

### Step 3: Define the Basic Unit
The basic unit of silicate is the silicate tetrahedron, which has the formula **SiO4**. In this structure, one silicon atom (Si) is surrounded by four oxygen atoms (O), forming a tetrahedral shape.

### Conclusion
Thus, the basic unit for zeolite, mica, asbestos, and feldspar is **silicate (SiO4)**.

### Final Answer
The basic unit for zeolite, mica, asbestos, and feldspar is **silicate (SiO4)**.

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