(POM) Chemical Changes Lesson

Chemical Changes

Did you ever make a "volcano" using baking soda and vinegar? What happens when the two substances combine? They produce an eruption of foamy bubbles. This happens because of a chemical change. A chemical change occurs when matter changes chemically into an entirely different substance with different chemical properties. When vinegar and baking soda combine, they form carbon dioxide, a gas that causes bubbles. It's the same gas that gives soft drinks their fizz.

Look at the picture below for some additional examples of chemical changes.  

Chemical Changes Examples: See description

Chemical Change description Links to an external site.

How can you tell whether a chemical change has occurred?  

  • Produces bubbles
    • Be careful not to confuse it with boiling.  With boiling, you are heating up the particles and it is changing phases...from a liquid to a gas.  
    • When you add vinegar and baking soda there is no heat and there are no gases within either original substance...therefore you know a new gas has been formed.
  • Turns cloudy
  • Temperature change
  • Color change
  • Change in smell or taste

Watch this video on Chemical and Physical Reactions.

How well did you understand the information presented above?

Can you identify whether a physical or chemical change is occurring in the examples below?

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