1. Chemical Interactions

2. Investigation #1 Substances

3. Chemistry Chemistry is the study of substances and their interactions.

4. Substance A substance is a form of matter with a unique composition and distinct properties. --- There are millions of different substances on Earth; each is unique.

5. Substances can be represented with: 1. common names --- sugar 2. chemical names --- sucrose 3. chemical formulas --- C 12 H 22 O 11

6. Mixture A mixture is made when two or more substances are mixed together, not chemically combined. ---- A mixture can be separated. – trail-mix is a great example. The M&M’s do NOT react with the raisins, they are just “together”.

7. Observations The foundation of scientific investigation is careful and precise observation. -- Be specific with your descriptions; include as much detail as possible.

8. Chemical Reaction A chemical reaction is a term used to describe a process where original substances are changed into a new substance or new substances. ---- There will always be a signal that a chemical reaction has occurred. ----- No signal, no reaction.

9. Chemical Reaction The substances that go into the reaction are called the “REACTANTS”. -- This shouldn’t be difficult to remember! Reactants, well they react!

10. Chemical Reaction What is produced after the reaction are called the “PRODUCTS”. -- This shouldn’t be confusing either! Products are produced!

11. Signals of a Reaction There are four main signals that tell you a chemical reaction has taken place. 1. Change in color. 2. Production of heat and/or light. 3. Formation of a solid. 4. Production of a gas.

12. More About the Signals

13. Change in Color The products end up a different color than the original reactants. -- This does not include any item that is painted or dyed. Example…. The shiny metal iron reacts with oxygen to form rust; a red- brown color.

14. Change in Color Video

15. Production of Heat and/or Light The reaction generates a change in temperature and/or produces visible light. -- Combustion is the most common example of this. Fireworks are tiny shards of metal that quickly combine with oxygen to burn; each piece is made of a different substance and burns a different color. Each is significantly “hotter” than before and you can easily view the light.

16. Production of Light Video

17. Formation of a Solid This signal is common when particular liquids are combined together. Solids form and quickly settle to the bottom of the container.

18. Forming of a Solid Video

19. Forming of a Gas The reaction generates a gas; most often visible in the form of bubbles. -- A good example can be viewed when you add a little baking soda to vinegar. The bubbles made (Carbon dioxide gas) are a product of the chemical reaction. When the bubbling stops you have produced a gas and a new liquid; both are unique substances different from the vinegar and baking soda that you started with.

20. Forming of a Gas Video (part 1)

21. Forming of a Gas Video (part 2)

22. More to Come This is just the first chapter of our adventure! Stay tuned for more! Ask questions, seek answers, explore, and attempt to understand why things are as they are. An understanding of basic chemistry is a really cool thing! It allows you to see this world in a very different way!