Which term describes the attraction of different molecules, such as water to glass?

• A. Adhesion
• B. Cohesion
• C. Covalent
• D. Metabolism

Answer: (A)

The main idea here is the difference between attractions that occur between unlike substances versus within a substance. Adhesion describes the attraction between different materials, such as water molecules sticking to a glass surface. Water is polar, and the glass surface can present charges or hydrogen-bonding sites, so water molecules cling to the glass, creating phenomena like a meniscus.

Cohesion, by contrast, is the attraction between like molecules—water molecules sticking to other water molecules. Covalent refers to a type of chemical bond where atoms share electrons, which is a chemical bond within or between molecules, not the general attraction between different substances. Metabolism is the set of chemical reactions that sustain life, not about how substances attract each other.