Which intermolecular forces are most significant in water (H_2O)?

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

Answer: (A)

Verified step by step guidance

1. Step 1: Identify the molecular structure of water (H\_2O). Water is a polar molecule with a bent shape due to the two lone pairs on oxygen, which creates a permanent dipole moment.
2. Step 2: Recognize the types of intermolecular forces possible in water. These include London dispersion forces (present in all molecules), dipole-dipole interactions (due to polarity), and hydrogen bonding (a special, strong dipole-dipole interaction involving H bonded to highly electronegative atoms like O, N, or F).
3. Step 3: Understand that ionic bonding is not an intermolecular force but a type of intramolecular bond found in ionic compounds, so it is not significant in molecular water.
4. Step 4: Evaluate which forces are most significant in water. Because water has hydrogen atoms bonded to oxygen, it exhibits strong hydrogen bonding, along with dipole-dipole interactions and London dispersion forces.
5. Step 5: Conclude that the most significant intermolecular forces in water are hydrogen bonding, dipole-dipole interactions, and London dispersion forces.