Elements, Compounds, and Mixtures
MATTER Elements Compounds Mixtures Matter can be split into three different groups: Elements Compounds Mixtures Matter is : Anything that has MASS and VOLUME
ELEMENT Definition: A pure substance that is made of only a single type of atom. Examples: Gold, Iron, Aluminum, Oxygen SEPARATING ELEMENTS: Cannot be broken apart under normal lab conditions. (heating, exposure to acids, exposure to electricity)
COMPOUND Definition: A single molecule of two or more ELEMENTS in fixed amounts. Properties are different than the elements that make it. Examples: Salt, Sugar, Vinegar, Glass, Water SEPARATING COMPOUNDS: Takes a HUGE amount of energy. Needs to be done chemically.
Molecule Definition: smallest piece of a compound that maintains its properties.
MIXTURE Definition: Combination of: two or more elements OR two or more compounds OR elements and compounds ***individual ingredients KEEP THEIR PROPERTIES ***mixtures are NOT pure substances SEPARATING MIXTURES: Easily separated physically (evaporation, strainer, pick out pieces, etc.) Properties of a mixture VARY. (different throughout)
Which is a mixture? Which is a compound? TRY IT OUT Which is a mixture? Which is a compound? Salad Soil Water (H2O) Salt and pepper Oxygen Ocean Water Air Vinegar and oil
Two types of MIXTURES Heterogeneous Unevenly mixed Does not appear to be the same throughout Most mixtures are heterogeneous EXAMPLES: Sand, Trail Mix, Salad Dressing Homogeneous Evenly mixed Appears to be the same throughout EXAMPLES: Saltwater, Syrup
Homogeneous vs. Heterogeneous
mixture of compounds MC mixture of elements ME element E mixture of elements/compounds MEC mixture of compounds MC compound C element E mixture of elements/compounds MEC mixture of compounds MC compound C
vinegar silicon dioxide (glass) baking soda sodium chloride (table salt)
The Big Idea The Big Idea: atoms (elements) molecules (compounds) group together (in different combinations) to form mixtures Combine to form
Types of Mixtures Solutions Suspensions Colloids
Solutions A solution is a mixture in which particles are spread evenly throughout and appears to be a single substance A solution is not a chemical change The particles are so small they never settle out; they cannot be filtered out Solutions are HOMOGENEOUS.
Solutions (continued) Solute: A substance whose particles are dissolved in a solution. Solvent: A substance in which a solute dissolves. Largest amount in a solution. Water is the universal solvent. Examples: Saltwater, Apple Juice
Solute & Solvent
Which is Which? TRY IT OUT Identify the solvent, solute, and solution Lemon juice + water + sugar= lemonade Carbon dioxide + water + syrup = soda Water + salt = salt water
Types of Solutions Gas in Gas (air / oxygen in nitrogen) No notes here- just listen!!! Gas in Gas (air / oxygen in nitrogen) Gas in Liquid (soda) Liquid in Liquid (antifreeze / alcohol in water) Solid in Liquid (salt water) Solid in Solid (brass / zinc in copper)
Heating: causes particles to move out more quickly How to Dissolve Faster No notes here- just listen!!! Mixing: by stirring or shaking causes the particles to move out more quickly Heating: causes particles to move out more quickly Crushing: increases the amount of surface area the solute has with the solvent
Suspensions A mixture in which the particles are evenly dispersed and are large enough to settle Can be separated by passing it through a filter Suspensions are HETEROGENEOUS. Examples: paints; salad dressings; medicines; muddy water; dusty air; snow globe
Colloids A mixture in which the particles are not dissolved, but dispersed throughout and not large enough to settle out or to be filtered out Colloids have properties of both suspensions and solutions Examples: milk; mayonnaise; stick deodorant; gelatin; whipped cream
ECM Station Activity You will travel to different stations today. At each station, there is a substance. For each station: Table # Identify object (what is it?) E,C,M (element, compound, mixture?) WHY? (what property/characteristic makes it an E,C, or M?