Unit 4: Structure of Molecules

What is the shape of a molecule with a central atom surrounded by four bonds and no lone pairs?

• A) Linear
• B) Trigonal planar
• C) Tetrahedral
• D) Octahedral

Answer: C) Tetrahedral

Which of the following molecules exhibits a bent shape?

• A) Methane (CH₄)
• B) Carbon dioxide (CO₂)
• C) Water (H₂O)
• D) Ammonia (NH₃)

Answer: C) Water (H₂O)

What is the bond angle in a molecule with a trigonal planar geometry?

• A) 90°
• B) 109.5°
• C) 120°
• D) 180°

Answer: C) 120°

Which type of hybridization is present in a molecule with a tetrahedral shape?

• A) sp
• B) sp²
• C) sp³
• D) sp³d

Answer: C) sp³

In a molecule with a linear geometry and two double bonds, the central atom is likely to be:

• A) Carbon
• B) Nitrogen
• C) Oxygen
• D) Sulfur

Answer: A) Carbon

What is the molecular geometry of a molecule with three bonds and one lone pair around the central atom?

• A) Tetrahedral
• B) Trigonal pyramidal
• C) Trigonal planar
• D) Linear

Answer: B) Trigonal pyramidal

Which of the following molecules has a triple bond?

• A) Ethene (C₂H₄)
• B) Acetylene (C₂H₂)
• C) Methane (CH₄)
• D) Ethane (C₂H₆)

Answer: B) Acetylene (C₂H₂)

In which molecule does the central atom exhibit sp² hybridization?

• A) Methane (CH₄)
• B) Water (H₂O)
• C) Formaldehyde (CH₂O)
• D) Ammonia (NH₃)

Answer: C) Formaldehyde (CH₂O)

Which of the following is true about the bond angles in a molecule with an octahedral geometry?

• A) The bond angles are 90° and 180°.
• B) The bond angles are 120° and 180°.
• C) The bond angles are 109.5°.
• D) The bond angles are 90° and 120°.

Answer: A) The bond angles are 90° and 180°.

What type of molecular shape does a molecule with two bonding pairs and two lone pairs around the central atom exhibit?

• A) Linear
• B) Tetrahedral
• C) Bent
• D) Trigonal planar

Answer: C) Bent