|Mixtures are combination of two or more substances where each substance retains its individual physical properties. There are two classes of mixtures: homogeneous and heterogeneous. Homogeneous mixtures have a constant composition whereas heterogeneous mixtures do not. Another name for a homogeneous mixture is a solution. Two subclasses of heterogeneous mixtures are suspension and colloids. How these classes differ is based on particle size. Suspensions have the largest particles and solutions have the smallest. Colloid particle size varies between suspension-size and solution-size. This quiz will cover the basics of mixtures. Select the best answer from the given choices. Good luck.