The maximum covalency of carbon is

Options

A. 2
B. 3
C. 4
D. 5

Answer

To determine the maximum covalency of carbon, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Atomic Number and Electron Configuration of Carbon:**
- Carbon has an atomic number of 6, which means it has 6 electrons.
- The electron configuration of carbon is 1s² 2s² 2p².

2. **Analyze the Valence Electrons:**
- The outermost shell (n=2) contains 4 electrons (2 in the 2s subshell and 2 in the 2p subshell).
- Therefore, the valence electrons of carbon are 4.

3. **Consider the Excited State:**
- In the excited state, one of the 2s electrons can be promoted to the 2p subshell.
- This results in the configuration: 2s¹ 2p³.
- Now, carbon has 4 unpaired electrons (1 in 2s and 3 in 2p).

4. **Determine the Maximum Number of Bonds:**
- Each unpaired electron can form a covalent bond.
- Since there are 4 unpaired electrons, carbon can form a maximum of 4 covalent bonds.

5. **Examples of Covalent Bonds:**
- In methane (CH₄), carbon forms 4 single bonds with hydrogen, contributing 4 electrons.
- In ethylene (C₂H₄), each carbon forms 4 bonds (3 sigma and 1 pi bond), still maintaining a maximum of 4 covalent bonds.

6. **Conclusion:**
- Therefore, the maximum covalency of carbon is 4.

### Final Answer:
The maximum covalency of carbon is **4**.

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