CHEM 004A Lecture 15: Chem - Chap 11 - Solutions and Colloids

(a) Do colloids made only of gases exist? Why or why not? (b) In the 1850’s, Michael Faraday prepared ruby-red colloids of gold nanoparticles in water that are still stable today. These brightly colored colloids look like solutions. What experiment(s) could you do to determine whether a given colored preparation is a solution or colloid?

- homogeneous solutions must be uniform in appearance.
- a solute is part of a solution that dissolves
- either the solvent or the solute in every solution must beliquid
- colloids are solutions

Define the following liquid mixtures as suspensions, colloids, or solutions.

a. Water + pepper –

b. Water + benzoic acid –

c. Water + sodium chloride –

d. Isopropanol + sucrose –