Which is the strongest type of intermolecular force present between separate H2O molecules?

• A. Dipole-dipole interactions
• B. London dispersion forces
• C. Hydrogen bonding
• D. Ion-dipole interactions

Answer: (C)

Verified step by step guidance

1. Identify the types of intermolecular forces listed: London dispersion forces, dipole-dipole interactions, hydrogen bonding, and ion-dipole interactions.
2. Recall that London dispersion forces are weak forces present in all molecules due to temporary dipoles, but they are generally the weakest type of intermolecular force.
3. Understand that dipole-dipole interactions occur between polar molecules where permanent dipoles attract each other, which are stronger than London dispersion forces but weaker than hydrogen bonds.
4. Recognize that hydrogen bonding is a special, stronger type of dipole-dipole interaction that occurs when hydrogen is directly bonded to highly electronegative atoms like nitrogen, oxygen, or fluorine.
5. Note that ion-dipole interactions occur between ions and polar molecules, which is not applicable here since H2O molecules are neutral, so the strongest intermolecular force between separate H2O molecules is hydrogen bonding.