Which intermolecular forces are present in a molecule of CH\(_3\)OH (methanol)?

• A. Only dipole-dipole interactions and London dispersion forces
• B. London dispersion forces, dipole-dipole interactions, and hydrogen bonding
• C. Only hydrogen bonding
• D. Only London dispersion forces

Answer: (B)

Verified step by step guidance

1. Identify the types of atoms and bonds present in the molecule CH\(_3\)OH (methanol). Methanol contains carbon (C), hydrogen (H), and oxygen (O) atoms, with an -OH (hydroxyl) group attached to the carbon chain.
2. Determine if the molecule is polar. The presence of the electronegative oxygen atom bonded to hydrogen creates a polar O-H bond, making the molecule polar overall. This polarity allows for dipole-dipole interactions.
3. Check for hydrogen bonding. Hydrogen bonding occurs when hydrogen is directly bonded to highly electronegative atoms like oxygen, nitrogen, or fluorine. Since methanol has an O-H bond, it can form hydrogen bonds.
4. Consider London dispersion forces. These forces are present in all molecules due to temporary fluctuations in electron density, regardless of polarity.
5. Conclude that methanol exhibits all three intermolecular forces: London dispersion forces (present in all molecules), dipole-dipole interactions (due to molecular polarity), and hydrogen bonding (due to the O-H bond).