Carbon forms four covalent bonds by sharing its four valence electrons with four univalent atoms, e.g., hydrogen. After the formation of four bonds, carbon attains the electronic configuration of

Options

A. helium
B. neon
C. argon
D. krypton

Explanation

To solve the question, we will follow these steps:

### Step 1: Identify the Electronic Configuration of Carbon
Carbon has an atomic number of 6. Therefore, its electronic configuration can be written as:
- K shell (2 electrons)
- L shell (4 electrons)

So, the electronic configuration of carbon is **K2, L4**.

### Step 2: Understand Carbon's Valence Electrons
Carbon has 4 valence electrons in its outer shell (L shell). To achieve a stable electronic configuration, carbon needs to have a total of 8 electrons in its outer shell, which is known as the octet rule.

### Step 3: Formation of Covalent Bonds
To complete its octet, carbon forms covalent bonds by sharing its 4 valence electrons with 4 univalent hydrogen atoms. Each hydrogen atom contributes 1 electron to the bond.

### Step 4: Count the Total Electrons Around Carbon
After forming 4 covalent bonds with 4 hydrogen atoms, carbon shares 4 electrons (1 from each hydrogen). Now, carbon has:
- 4 of its own electrons
- 4 shared electrons from hydrogen

This gives a total of **8 electrons** around the carbon atom.

### Step 5: Determine the New Electronic Configuration
With 8 electrons in the outer shell, the new electronic configuration of carbon becomes:
- K shell (2 electrons)
- L shell (8 electrons)

Thus, the new configuration is **K2, L8**.

### Step 6: Relate to Noble Gas Configuration
The electronic configuration K2, L8 corresponds to the nearest noble gas, which is neon (Ne). Therefore, after forming four covalent bonds, carbon attains the electronic configuration of neon.

### Final Answer
After the formation of four bonds, carbon attains the electronic configuration of **neon**.

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