Mixtures are organized by particle size

Apuntes

Mixtures are organized by particle size and appearance. Mixtures are physical combinations of two or more substances. Matter Mixtures Pure Substances Heterogeneous Homogeneous Compounds Elements Heterogeneous mixtures: not a definite or uniform composition Heterogeneous Mixtures are organized into three categories. ✔ Heterogeneous mixtures (very large particles) ✔ Suspensions ✔ Colloids Contain particles over 1000 nm in size. Particles will settle unless constantly stirred. Can be separated by filtration Particles between 1 and 1000 nm in size. (can be seen under microscope) ✔ Particles do not settle ✔ Cannot be separated by filtration. ✔ Exhibit the Tyndall Effect Tyndall Effect- Particles in a colloid have the ability to scatter light Example: headlights in fog Can be used to distinguish between a colloid and a solution. Homogeneous Mixtures: Uniform appearance Example: Saltwater All homogeneous mixtures are solutions! A solution is a homogeneous mixture of two or more substances in a single phase. Solutions: ✔ Do not separate on standing ✔ Cannot be separated by filtration ✔ Do not scatter light Even though we have “homogenized” milk, if you look...