Mixtures, Solutions, Suspensions, & Colloid Notes

MATTER Heterogeneous mixture Homogeneous mixture Pure Substance No Is it uniform throughout? Yes Heterogeneous mixture Homogeneous mixture No Can it be separated by physical means? yes Pure Substance Homogeneous Mixture (solution) Can it be decomposed into other substance by a chemical process? No yes Compound Element

Mixture A mixture is 2 or more substances that aren’t chemically combined. Doesn’t react to form a compound. Ex: pizza is cheese, mushrooms, pepperoni, tomato sauce, & crust.

Mixture You can pick out the individual components of a mixture. Each item in the mixture keeps it’s identity. Ex: Toss Salad is lettuce, cheese, tomato, & dressing.

Mixtures may be: Homogenous - uniformly distributed particles. Ex: Crystal light in water.

Heterogeneous- unevenly distributed particles. Mixtures may be: Heterogeneous- unevenly distributed particles. Ex: ingredients on pizza or in toss salad.

Mixtures Mixtures don’t have definite ratio ( 1:1, 2:5, etc) of components. The components can vary in proportion.

Mixtures: 2- Separated by physical means. 1- No change in the original properties of the components. 2- Separated by physical means. 3-Formed by using any ratio of components.

Separating Mixtures Can separate by physical means: Spinning in a Centrifuge.

Centrifuge Ex. - Separates blood platelets from plasma Spinning in a circle causing the most dense material to settle to the bottom. Ex. - Separates blood platelets from plasma Ex. - Separating different components of atomic particles.

Centrifuge separates blood platelets

Particles are evenly distributed throughout. Solutions Particles are evenly distributed throughout. Same appearance & properties throughout the mixture. Particles in a solution are so small they never settle out & can’t be separated by filtering.

Solute/Solvent Solute is the substance that is dissolved. Solvent is the substance solute is dissolved in. FYI - When 2 liquids or 2 gases are combined into a solution, the substance with the greater amount is the solvent. Ex: air (oxygen in nitrogen) or antifreeze (alcohol in water) or brass (zinc in copper).

Solute/Solvent

Solutions may be: Solid in liquid (salt in H2O) Liquid in liquid (antifreeze) Gas in gas (Air O in N) Gas in liquid (soda CO2 in H2O) Solid in solid (Brass=Cu in Zn)

Concentration Is expressed as grams solute/milliliter of solvent. Dilute is less solute per unit of solvent. Concentrated is more solute per unit of solvent.

Saturated Saturated means the solution holds all the solute it can hold at a specific temperature & pressure.

Solubility Is the ability of solute to dissolve in solvent at a certain temperature and pressure. Most solids are more soluble in liquid as the temperature goes up (the solute particles are further apart). Most gases are less soluble in liquid as temperature goes up (the gas more easily escapes from the liquid).

Solubility Mix or stir (get particles moving not clumped together) Ways to increase solubility are: Mix or stir (get particles moving not clumped together) Heat (increase the particles average kinetic energy) Crush ( increase surface area)

Suspension Can separate by passing through a filter. A mixture of particles dispersed in a liquid or a gas but large enough they will eventually settle out. Can separate by passing through a filter. Ex: Snow globe, Italian Dressing, dirt particles in a container of water.

Suspension

Colloid A mixture that the particles sizes are between a solution & a suspension. Particles are dispersed throughout but aren’t heavy enough to settle out. Can’t be separated by filtering. Ex: milk, jello, whip cream, & butter.

Colloid