A stable physical mixture of two or more substances in a solvent is a(n) _____.

• A. suspension
• B. solution
• C. colloid
• D. mixture

Answer: (B)

In a stable, homogeneous blend where a solute dissolves in a solvent, you have a solution. The composition is uniform throughout because the solute molecules are completely dissolved, forming a single phase that looks the same from top to bottom. This means the mixture won’t separate on standing and the particles are too small to see or filter out easily.

A suspension, by contrast, contains larger particles that are dispersed but not dissolved; these particles will eventually settle out, making the mixture heterogeneous. A colloid has intermediate-sized particles that stay dispersed and may scatter light, but they aren’t truly dissolved and don’t settle quickly. A general mixture could be anything, including heterogeneous blends, and doesn’t imply that dissolution has occurred.