Which statement is wrong ?

Options

A. Feldspars are not aluminosilicates
B. Beryl is an example of cyclic silicate
C. `Mg_(2) SiO_(4)` is orthosilicate
D. Basic structural unit in silicates `SiO_(4)^(4-)` is the tetrahedron

Answer

To determine which statement is wrong, let's analyze the statements provided in the question step by step.

### Step 1: Analyze the first statement
**Statement**: Feldspar is not alumino silicate.

**Analysis**: Feldspar is indeed an alumino silicate mineral. It is one of the most abundant minerals in the Earth's crust and consists of aluminum silicate combined with other elements like potassium, sodium, or calcium.

**Conclusion**: This statement is **wrong**.

### Step 2: Analyze the second statement
**Statement**: Birayil is an example of cyclicate.

**Analysis**: The term "Birayil" seems to be a misspelling or mispronunciation. However, if we assume it refers to a cyclic silicate, then cyclic silicates are indeed a class of silicates where the silicate tetrahedra are linked in a ring structure.

**Conclusion**: This statement is **correct** if it refers to a cyclic silicate.

### Step 3: Analyze the third statement
**Statement**: Mg2SiO4 means magnesium Mg2SiO4.

**Analysis**: The formula Mg2SiO4 represents a silicate mineral known as forsterite, which is a type of olivine. It consists of magnesium and silicate ions.

**Conclusion**: This statement is **correct**.

### Step 4: Analyze the fourth statement
**Statement**: The basic structural unit in silicates is SiO4 tetrahedron.

**Analysis**: This statement is accurate. The basic unit of silicates is indeed the silicate tetrahedron (SiO4), where one silicon atom is surrounded by four oxygen atoms in a tetrahedral arrangement.

**Conclusion**: This statement is **correct**.

### Final Conclusion
After analyzing all the statements, the only statement that is wrong is the first one: "Feldspar is not alumino silicate."

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