1. Mixtures
…matter that contains two or more substances that differ in physical and chemical properties.

2. Pure substances are:
Substance that has definite chemical and physical properties.
Some examples
Gold (Au), oxygen (O), iron (Fe), sulfur (S)
Water (H2O), salt (NaCl), hydrogen peroxide (H2O2)

3. Two types of mixtures: Heterogeneous:
-not well mixed, easy to separate.
Ex. a salad
Homogeneous:
-well mixed, hard to separate.
Ex. blood

4. Aqueous Solutions: Solutions that are solids dissolved in water.
Two parts of a solution:
Solute – substance being dissolved.
Solvent – substance doing the dissolving.

5. Some aqueous solutions can conduct electricity – Electrolytes.
Some do not – Nonelectrolytes.