Which types of intermolecular forces are present in methanol (CH3OH)?

• A. London dispersion forces, dipole-dipole interactions, and hydrogen bonding
• B. London dispersion forces and dipole-dipole interactions, but not hydrogen bonding
• C. Only dipole-dipole interactions
• D. Only London dispersion forces

Answer: (A)

Verified step by step guidance

1. Identify the molecular structure of methanol (CH3OH). It consists of a methyl group (CH3-) attached to a hydroxyl group (-OH).
2. Determine the types of intermolecular forces possible based on the molecular structure. Methanol is a polar molecule due to the electronegativity difference between oxygen and hydrogen in the -OH group, which creates a dipole moment.
3. Recognize that all molecules exhibit London dispersion forces (also called van der Waals forces) due to temporary fluctuations in electron density, so methanol will have these forces.
4. Since methanol is polar, it will also exhibit dipole-dipole interactions, which occur between the positive end of one polar molecule and the negative end of another.
5. Because methanol contains an -OH group, it can form hydrogen bonds, a special and strong type of dipole-dipole interaction that occurs when hydrogen is bonded to highly electronegative atoms like oxygen, nitrogen, or fluorine.