The bond angle in tetrahedral molecules such as tetrachloromethane is

1. Analyze the question The question asks for the bond angle in a tetrahedral molecule such as CCl₄ (tetrachloromethane).

2. Explain the concept (VSEPR theory) Electron pairs around a central atom repel one another and arrange themselves as far apart as possible. The shape depends on the number of bonding pairs and lone pairs:

• 2 pairs: linear, 180°
• 3 pairs: trigonal planar, 120°
• 4 pairs: tetrahedral, 109.5°
• 6 pairs: octahedral, 90°

3. Solution

• Carbon in CCl₄ has 4 valence electrons, and each forms a single covalent bond with a chlorine atom.
• That gives 4 bonding pairs and no lone pairs around carbon.
• Four electron pairs spread out as far as possible, giving a tetrahedral arrangement.
• The angle between any two C-Cl bonds is 109.5° (exactly cos⁻¹(−1/3) ≈ 109.47°).

Checking the other options:

• A (180°) is for linear molecules such as CO₂ or BeCl₂.
• C (105.5°) is close to the angle in water, which is about 104.5° because lone pairs squeeze the bond angle.
• D (90°) is found in octahedral molecules such as SF₆.

4. Answer The correct option is B. 109.5°.

5. Exam tip Remember the pattern: CH₄, CCl₄, NH₄⁺ all have 4 bonding pairs and 109.5°. If lone pairs replace bonding pairs, the angle shrinks: NH₃ is about 107° and H₂O is about 104.5°.