Physical vs. Chemical Changes

Chemical Changes!

Chemical changes are changes in the molecular structure of a substance. Usually in a Chemical Change, a new substance is formed. There are a few indicators that tell you that a chemical change has happened:

  1. Gas is produced (bubbles seen)
  2. Light is produced
  3. Change in color
  4. Change is temperature
  5. Precipitate formed (leftover substance)

Look for these pointers when you are deciding if a chemical change has happened. There is actually a way to remember if a Chemical Change has occurred. The hint is when you cook something, it is ALWAYS a Chemical Change. Some examples of Chemical Changes are toasting bread, mixing baking soda and vinegar, fireworks exploding, and burning paper. These all are Chemical Changes.

Physical Changes!

Physical Changes are any change in physical properties. Some physical properties are size, shape, color, and texture. Physical Changes do NOT form a new substance. The substance stays the same, but it changes some of its physical