Matter

Anything that has mass and occupies space. Made up of atoms. Has two major categories.

First Category Substances Have a definite and unique composition. Cannot be broken down by ordinary, physical means If they are broken down, the new material will not maintain the properties of the original material.

Substances have 2 sub-categories Elements Made up of ONLY one kind of atom. Examples: Copper Aluminum Helium All those on the Periodic Table

The Other Sub-category of Substances Compounds Made up of MORE THAN ONE KIND of atom. Chemically bonded together. Cannot be broken down by physical means. When broken down, the components do not resemble the original material. Example: Water, Carbon Dioxide, Sodium Chloride

2nd Category of Matter Mixtures Made up of more than one kind of atom, but there is no specific or definite ratio. Can be separated by physical means. Examples: Salt water, Pizza, Blood, Muddy water.

4 Sub-categories of Mixtures 1. Heterogeneous Mixtures Again, more than one kind of atom. Particles can easily be seen. Will not be the same throughout, different “phases”. Example: Pizza

Another sub-category of Mixtures 2. Homogeneous Mixtures The same throughout. Only one “phase”. Usually clear-ish. Also called solutions. Could be a mixture of gases or liquids. A beam of light is NOT visible when passing through a solution. Example: Tea, salt water

Yet another sub-category of Mixtures 3. Colloids Solid or solid-like particles are suspended in a liquid. Particles will not settle out. Although the particles are large, they are not heavy enough to settle on their own. A beam of light passing through a colloid IS visible. Example: Milk, fog, dust in the air.

And yet another sub-category of Mixtures 4. Suspensions Small, solid particles in a liquid. Particles will eventually settle out. Example: Muddy water

Properties of Matter Physical Properties Chemical Properties

Physical Properties Can be observed without changing the substance. Examples: Boiling point, freezing point, density, mass, volume, luster, hardness,

Chemical Properties Can ONLY be observed by chemical means. The substance MUST go through a chemical reaction. The “new” material will be unlike the original material. Something “NEW” is produced. Usually NOT reversible. Examples: Flammability, reactivity

Physical Changes Changes that matter will undergo that are reversible, at least somewhat. Nothing new is produced. Examples: Boiling, freezing, breaking, tearing, dissolving.

Chemical Changes Changes where the original material is been changed to something totally new. Examples: Burning, chemical bonds being either formed or broken. Usually energy is being released (gets hot) or absorbed (gets cold), or gas is given off.