Chemistry Unit 2 Classification of Matter Matter – Anything that has mass and takes up space

Matter

Matter Pure Substances Mixtures

Matter Pure Substances Mixtures Elements Compounds

Matter Pure Substances Mixtures Elements Compounds Homogeneous Heterogeneous

Pure Substances Made of only one type of matter.

Mixture Two or more types of matter physically combined. No definite ratio of particles.

Elements Made of only one type of atom. A complete list of all elements can be found on the Periodic Table.

Compounds Atoms of two or more elements, chemically combined in a definite ratio.

Homogeneous Mixtures Atoms of two or more elements, physically combined in no definite ratio. The same throughout. Must be a SOLUTION A solute dissolved in a solvent.

Heterogeneous Mixture Two or more types of atoms, physically combined in no definite ratio. Different throughout.

Classification of Mixtures Suspension – heterogeneous mixture; large particles. Ex. Snow globes, muddy water Colloid – heterogeneous mixture; small particles. Ex. Milk, butter, salad dressing Solution – homogeneous mixture; particles have dissolved. Ex. Saline, Kool Aid, Sweet tea

Tyndall Effect Light cannot be seen unless it reflects off of a surface. If you shine a beam of light through a mixture and the beam is visible, there must be particles in the mixture there to reflect the light. Suspensions and Colloids give a positive Tyndall Effect. Solutions do not.

Suspension Particles are usually large enough to be seen with the naked eye. Particles will settle out if allowed to stand. Particles can be removed if passed through a filter paper. Particles will cause a positive Tyndall Effect.

Colloid Particles are usually too small to be seen with the naked eye. Particles will not settle out of the mixture. Particles will pass unchanged through the pores of the filter paper. Particles will cause a positive Tyndall Effect.

Solution Particles are dissolved. Will not settle out if allowed to stand. Will not separate when filtered. Will not cause a positive Tyndall Effect.

Physical Properties Describe the physical attributes of matter. Examples: color, shape, size, texture, density, temperature, state or phase, smell, taste, boiling/melting/freezing points, magnetic attraction, solubility.

Physical Change A change in one of the physical attributes of a sample of matter. Does not change the chemical composition of the matter.

Chemical Properties Describes the way a sample of matter reacts in the presence of other matter. Examples: Oxidation, Corrosion, Hydrolysis, Combustion, Flammability, Reaction to Acid or Base.

Chemical Change A change in the chemical composition of a sample of matter. Always produces a new substance with new properties.