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

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.

Formation of PrecipitateOne 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

First set up your journal:Title: Precipitate Lab

Guiding Question: How do I know a chemical change happened?

Chart:

I notice…. I wonder….

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”

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”

Color ChangeA 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.

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:

I notice…. I wonder….

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”.

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”.

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.