Don T Mix up the Colors

Don’t mix up the colors

Introduction: Today’s lab will focus on proper lab practice. The experiment that you are performing is secondary to becoming familiar with proper lab procedures. In today’s lab you will be given three test tubes, each with a different colored liquid. Your task will be to get those different colors to stack on top of one another without mixing them. This is more challenging than you might imagine.

Objective: Follow all lab procedures. Always wear your goggles when handling chemicals.

Procedure:

1) Get the three test tubes and straw in the test tube rack from the front/side of the classroom. Also obtain a waste beaker.

2) Place your thumb or index finger of over the top of the straw and partially submerge the straw in one of the three colored liquids. Release your finger to allow the liquid to move up the straw and then put your finger back down to trap the liquid in place (you’ve done this before with your drinks at fast food restaurants).

3) Now move the straw to another test tube while holding your finger in place to ensure that the liquid remains in place.

4) Submerge the straw more deeply in the liquid in the next test tube and release your finger. The second liquid should now push the first liquid up the straw. If the two colors stack on top of each other in two distinct layers that do not mix, great! If they mix then dump the contents of your straw into the waste beaker and start over with step 2.

5) Repeat steps 2 through 4 until you have 3 distinct colors in three distinct layers in the straw. Once you have done this take a picture with your phone and then dump the contents of the straw into the waste beaker.

6) Dump the liquids from your test tubes and the waste beaker into the sink. Refill your test tubes with fresh liquids from the front of the classroom and return your setup to where you got it at the start of class.

Analysis: (Use the space below to create a data table as instructed)