Which statement best describes the effect of soap on hydrogen bonds in water?

• A. Soap forms covalent bonds with water molecules, replacing hydrogen bonds.
• B. Soap disrupts hydrogen bonds between water molecules, reducing surface tension.
• C. Soap strengthens hydrogen bonds between water molecules, increasing surface tension.
• D. Soap has no effect on hydrogen bonds in water.

Answer: (B)

Verified step by step guidance

1. Understand that water molecules are held together by hydrogen bonds, which are intermolecular attractions between the hydrogen atom of one water molecule and the oxygen atom of another.
2. Recognize that surface tension in water arises because of these hydrogen bonds, creating a 'skin' on the water surface.
3. Know that soap molecules have a hydrophilic (water-attracting) head and a hydrophobic (water-repelling) tail, allowing them to interact with water and disrupt the hydrogen bonding network.
4. Realize that when soap is added to water, the soap molecules insert themselves between water molecules, interfering with the hydrogen bonds and thus reducing the overall hydrogen bonding.
5. Conclude that this disruption of hydrogen bonds by soap molecules leads to a decrease in surface tension of water, which is why soap helps water spread and clean surfaces more effectively.