Which of the following is an electrovalent linkage ?

Options

A. `CH_(4)`
B. `MgCl _(2)`
C. `SiCl_(4)`
D. `BF_(3)`

Answer

To determine which of the given compounds has an electrovalent linkage (ionic bond), we can follow these steps:

### Step 1: Understand Electrovalent Linkage
Electrovalent linkage, also known as ionic bond, is formed when there is a complete transfer of electrons from one atom to another. This typically occurs between a metal and a non-metal.

### Step 2: Analyze Each Compound
We will analyze each of the given compounds to identify if they contain an ionic bond.

1. **Methane (CH₄)**:
- Both carbon (C) and hydrogen (H) are non-metals.
- The bond formed is a covalent bond due to the sharing of electrons.
- **Conclusion**: No electrovalent linkage.

2. **Magnesium Chloride (MgCl₂)**:
- Magnesium (Mg) is a metal and chlorine (Cl) is a non-metal.
- An ionic bond is formed here as magnesium transfers electrons to chlorine.
- **Conclusion**: This compound has an electrovalent linkage.

3. **Silicon Tetrachloride (SiCl₄)**:
- Both silicon (Si) and chlorine (Cl) are non-metals.
- The bond formed is a covalent bond due to the sharing of electrons.
- **Conclusion**: No electrovalent linkage.

4. **Boron Trifluoride (BF₃)**:
- Both boron (B) and fluorine (F) are non-metals.
- The bond formed is a covalent bond due to the sharing of electrons.
- **Conclusion**: No electrovalent linkage.

### Step 3: Identify the Correct Answer
After analyzing all the compounds, we find that only **Magnesium Chloride (MgCl₂)** has an electrovalent linkage.

### Final Answer
The compound that exhibits an electrovalent linkage is **MgCl₂** (option 2).

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