17.1 Composition of Matter

Matter- something with mass that takes up space

Substance or Mixture? Substance - an element or compound that cannot be broken down and still maintain properties. 1.Element- a substance with all atoms alike – Examples: helium, gold, nitrogen 2.Compound- a substance with the atoms of two or more elements combined in fixed proportions Examples: water H2O, carbon dioxide CO2

Substance or Mixture? Mixture- material of two or more substances that can easily be separated. Examples: coke, pizza, salsa

Heterogeneous or Homogeneous Mixture Heterogeneous mixture- materials are easily distinguished. – Examples: concrete, granola bar, pizza Homogeneous mixture- evenly blended mixture – Examples: unopened soda, vinegar

Mixtures that are fluids Solutions- homogeneous mixture, particles never settle and are too small for microscope. – Parts of a solution: Solute: the material being dissolved Solvent: the material doing the dissolving 3 ways to dissolve solids into liquids more quickly: – Increase temperature – Shake or stir – Break solute into smaller particles

Tyndall Effect- the scattering of light by fine particles in a fluid mixture. (Does not occur in solutions, particles are too small) Examples: headlight in fog, blue irises in human eyes Suspensions- heterogeneous mixture, larger particles will settle to bottom and liquid will clear. Example: muddy pond water