Cohesive forces in liquid water occur when:

• A. The H atoms on molecules of H₂O hydrogen bond to O atoms on adjacent molecules of H₂O.
• B. The H atoms on molecules of H₂O hydrogen bond to other H atoms on adjacent molecules of H₂O.
• C. The atoms on molecules of H₂O hydrogen bond to other O atoms on adjacent molecules of H₂O.
• D. None of the above are correct.

Answer: (A)

Verified step by step guidance

1. Understand the concept of hydrogen bonding: Hydrogen bonds are weak interactions that occur between a hydrogen atom covalently bonded to an electronegative atom (like oxygen) and another electronegative atom.
2. Identify the structure of a water molecule: Water (H2O) consists of two hydrogen atoms and one oxygen atom. The oxygen atom is more electronegative, creating a partial negative charge, while the hydrogen atoms have a partial positive charge.
3. Recognize the nature of cohesive forces: Cohesive forces refer to the attraction between molecules of the same substance. In water, these forces are primarily due to hydrogen bonding.
4. Determine the correct hydrogen bonding interaction: In liquid water, the hydrogen atoms of one water molecule form hydrogen bonds with the oxygen atoms of adjacent water molecules, not with other hydrogen atoms.
5. Evaluate the given options: The correct answer is that the hydrogen atoms on molecules of H2O hydrogen bond to oxygen atoms on adjacent molecules of H2O, which aligns with the nature of hydrogen bonding and cohesive forces in water.