Which type is a homogeneous macroscopic mixture?

Which type is a homogeneous macroscopic mixture?

• A. Solutions
• B. Suspensions
• C. Colloids
• D. All of the above

Answer: (A)

A homogeneous mixture that looks the same throughout at everyday scales is a solution. In a solution, the solute dissolves completely in the solvent, so the particles are distributed uniformly on the molecular level. You can’t distinguish the components by eye or with a light microscope, and the mixture doesn’t settle or separate over time—hence it’s uniform on a macroscopic scale. Suspensions have large particles that are not dissolved; they tend to settle out and separate, so they are not uniform throughout. Colloids have intermediate-sized particles that often appear uniform to the naked eye but are not truly dissolved; they can scatter light (the Tyndall effect) and contain a dispersed phase, so they aren’t a true homogeneous macroscopic mixture. That’s why the best choice is a solution.

A homogeneous mixture that looks the same throughout at everyday scales is a solution. In a solution, the solute dissolves completely in the solvent, so the particles are distributed uniformly on the molecular level. You can’t distinguish the components by eye or with a light microscope, and the mixture doesn’t settle or separate over time—hence it’s uniform on a macroscopic scale.

Suspensions have large particles that are not dissolved; they tend to settle out and separate, so they are not uniform throughout. Colloids have intermediate-sized particles that often appear uniform to the naked eye but are not truly dissolved; they can scatter light (the Tyndall effect) and contain a dispersed phase, so they aren’t a true homogeneous macroscopic mixture. That’s why the best choice is a solution.