Which statement is wrong

Options

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

Answer

To determine which statement is wrong, we will analyze each statement one by one.

### Step 1: Analyze the First Statement
**Statement:** "Barrel is an example of cyclic silicate."

- **Explanation:** The chemical formula for barrel is given as \( \text{Be}_3\text{Al}_2\text{Si}_6\text{O}_{18} \). This compound indeed represents a cyclic silicate, also known as a ring silicate. Therefore, this statement is **correct**.

### Step 2: Analyze the Second Statement
**Statement:** "Mg2SiO4 is ortho silicate."

- **Explanation:** The compound \( \text{Mg}_2\text{SiO}_4 \) is known as magnesium ortho silicate. This is a well-established classification in silicate chemistry. Thus, this statement is also **correct**.

### Step 3: Analyze the Third Statement
**Statement:** "The basic structural unit of silicate is SiO2 tetrahedral."

- **Explanation:** The basic structural unit of silicates is actually the tetrahedral ion \( \text{SiO}_4^{4-} \). While \( \text{SiO}_2 \) is a common form of silicon dioxide, the tetrahedral representation is more accurate for describing the silicate structure. Therefore, this statement is **incorrect** as it misrepresents the basic unit.

### Step 4: Analyze the Fourth Statement
**Statement:** "Feldspars are not alumino silicate."

- **Explanation:** Feldspars are indeed a group of aluminosilicate minerals, which means they contain aluminum, silicon, and oxygen in their structure. Therefore, this statement is also **incorrect**.

### Conclusion
From the analysis:
- The first statement is correct.
- The second statement is correct.
- The third statement is incorrect.
- The fourth statement is incorrect.

Thus, the wrong statements are the third and fourth statements.

### Final Answer
The wrong statements are:
- "The basic structural unit of silicate is SiO2 tetrahedral."
- "Feldspars are not alumino silicate."

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