Formation of Precipitate Lab & M.O.M. Color Lab

1. Formation of Precipitate Lab& M.O.M. Color Lab

2. Signs of Chemical Change • There are a number of observations that indicate a chemical reaction has occurred. • Today you will observe some signs of chemical change in a lab.

3. Formation of Precipitate One is the formation of a precipitate. A precipitate is a solid formed in a chemical reaction that is different from either of the reactants. Liquid + Liquid  New Solid formed

4. First set up your journal: Title: Precipitate Lab Guiding Question: How do I know a chemical change happened? Chart:

5. Next… • Write in your I Notice chart what you observe about your materials. • Draw a picture of what everything looks like Before we test. Label your picture “Before”

6. Then… • Add a few drops of solution A to solution B using the pipette (a fancy word for dropper). • In your journal write what you Notice and what you Wonder. Look closely. • Illustrate what you see After mixing. Label your picture “After”

7. Color Change A color change may also indicate that a chemical reaction has occurred. A reaction has occurred if two solutions are mixed and there is a color change that is not simply the result of a dilution of one of the reactant solutions. We call this an unexpected color change.

8. Set up a New pg in your Journal… Title: M.O.M. Colors Lab Guiding Questions: What type of change happens in this lab? Explain how you know it is a physical or chemical change? Chart:

9. Then… • Observe what materials you are going to use and write about them in your I Notice chart. • Draw a Before picture and label it “before”.

10. Next… • You will need to measure 20 mL of vinegar in the graduated cylinder. • When you have 20 mL- pour the vinegar into the M.O.M. solution. • Observe what happens and write about what you see in your I notice… I wonder… chart. • Draw a picture of what you saw and label it “after”.

11. Finally… • You will need to measure 20 mL of vinegar in a graduated cylinder again. • Pour the 20 mL of vinegar into the M.O.M. solution one last time to see what happens. • Draw and write what you saw. • How can we change this lab? • Answer your Guiding Questions for your ticket out! Show them to your teacher after you clean up.