Main categories of Substances

​1- Pure Substances

• This is either an element or a compound.

• Elements are easy to identify-just look at the periodic table!

• Compounds are elements that are chemically bonded together.
  
  

Sodium Chloride (NaCl)
Water (H₂O)
Carbon Dioxide (CO₂)
Hydrochloric Acid (HCl)
Baking Soda (NaHCO₃₎

​Compounds

Carbon C
Hydrogen H
Oxygen O
Nitrogen N
Neon Ne

​Elements

Examples of Pure Substances:

Main Categories of Substances:

​2: Mixtures

• Heterogeneous-a mixture in which the composition is not uniform throughout the mixture.

• Homogeneous- a mixture in which the composition IS uniform throughout-the individual parts can not be identified.

Brass (solid-mixture of metals)
Salt water (liquid-salt usually doesn't settle out)
Air (gas-can't distinguish the different gases in the air)

​Homogeneous

Tossed Salad (solid- parts can be separated)
Hot Cocoa (liquid-because the cocoa will settle to the bottom)
Smog (gas-the pollution is not evenly distributed in the air)

Heterogeneous

examples of mixtures (Solids, liquids, and Gases)

Solutions: another word for Homogeneous

Solutes, Solvent, and Solution

Solute + Solvent = Solution
The solute gets dissolved in something else.
The Solvent does the job of dissolving the solute.
Examples:
Salt + Water = Salt water