2 Mixtures and Solutions A mixture is a combinationof two or more components thatare NOT chemically combined,and retain their identities.Mixtures can be physically separated. The identities of the substances DO NOT change.A homogeneous mixture is also called asolution.
3 MixturesWhen a mixture’s components are easily recognizable, such as pizza, it is called a heterogeneous mixture.In a homogeneous mixture suchas chocolate milk, the component particles cannot be distinguished,even though they still retain theiroriginal properties.
4 Mixtures Common Techniques for Separating Mixtures Distillation – separates a mixture based on boiling points of the component.Examples :saltwatercrude oil into gasoline and keroseneMagnet – separates iron from other objects.Centrifuge – spins and separates according to densities.
5 SolutionsA mixture that appears to be a single substance but is composed of particles of two or more substances that are distributed evenly amongst each other.A solution may be liquid, gaseous, or solid.Examples of solutionsLiquid - seawaterGas - airSolid - alloys
6 Solutions Dissolving – The process in which particles of substances separate andspread evenly amongst each other.Solute – substance that is dissolved. A solute issoluble, or able to dissolve.A substance that is insoluble is unable todissolve, forms a mixture that is nothomogeneous, and therefore NOT a solution.Solvent – substance in which solute is dissolved.
7 SolubilityThe solubility of a solute is the amount of solute needed to make a saturated solution using a given amount of solvent at a certain temperature.Solubility is usually expressed in grams of solute per 100 ml of solvent (g/100ml)Three (3) methods that affect solubilityMixing, stirring, or shakingHeatingCrushing or grinding
8 Suspension A mixture in which particles of a material are dispersed through-out a liquid or gas but are largeenough that they settle out.Particles are insoluble, so they DO NOT dissolve in the liquid or gas.Particles can be separated using a filter.Examples:Salad dressingMedicines that say“shake well before use”
9 ColloidsA mixture in which the particles are dispersed throughout but are not heavy enough to settle out.Made up of solids, liquids and gases.Examples :MayonnaiseStick deodorantmilk