Let’s Make Slime or Ooey, Gooey Polymers

Category: Chemistry | Career: Chemist

Supplies per pair of students:

Tablespoon spoon
popsicle sticks or coffee stir sticks
paper towels
Borax
1-cup measure
two plastic containers (1-cup yogurt containers work well, if used, you can omit measuring water and just have girls fill water to near top)
white glue
goggles
cold water
plastic bags to take slime home in
food coloring (this can be shared by all).

If the students are divided into groups larger than two, remember to provide supplies and allow time for each girl to make some slime.

I. Introduction (5 minutes): Hello, my name is Dr. Carol Carbonian. I am a chemist. When I was eleven I got a lab set for my birthday. I loved playing with it, but it wasn't until high school chemistry that I thought about it as a career. Now I work in an Arco laboratory. Today I would like to share with you something fun you can do with chemistry.

II. Defining Career (5 minutes): Before we start our experiment, let's talk a bit about chemists. What do you think a chemist is? [Writes down about five ideas from the students on a chalkboard.] Good, those are great definitions. A chemist is a person who studies the composition and structure of substances and the changes they undergo. Now, what do you think a chemist does every day? [Writes about five of these down on the board also.] I do some of these things, like [points out on the board]. I also [continues with some things she does at work].

III. Hands-on Activity (25 minutes): Now that you know some of the things I do as a chemist, let's do something that involves chemistry! In front of each pair of you is some glue, a white powder called borax, water, two empty containers, a mixing stick and goggles. Notice now, the texture, consistency and smell of all of these ingredients. The exciting part about experiments is watching how things change when a chemical reaction occurs. So, to get started, I would like one person from each team to pour 1 cup of water into one of the containers. Now, your lab partner will add 1 spoonful of Borax. Stir with the mixing stick for about 3 minutes, to dissolve the Borax. While you are stirring, I will come around to answer any questions you might have. [During this time, walks around the room to answer questions and interact with the groups.] (after 3 mins) OK, you can stop stirring. Don't worry if there are some grains at the bottom of your cup. Now, one of you pour 4 spoonfuls of glue into the second container. Bring it to the front of the room here and add 2 or three drops of color. (After color) Stir the glue to mix in the color. Now, one of you measure 1 spoon of the borax/water. Here is the fun part. Stick your fingers in there and mush it around. Notice what happens to the mixture because we will be talking about that after. Let the girls mix and mash the goo for about a minute to really get it to a slimy state. All right, I can see that you are all natural-born chemists! Before we talk about what just happened, I would like each group to make another batch of slime. But, to see what effect borax has, we will now mix one more spoonful of borax into our borax/water. Stir that up for a few minutes to dissolve it. Now, repeat the procedure. That means, take out the goo-ball and put it into the plastic bag while you make a new batch. Remember, 4 spoons of glue for 1 spoon of borax/water. But, this time add the 2-3 drops of color to the spoon of borax/water.

IV. Closing (15 minutes): Now that we all have our own slime, let's talk about what happened. As scientists we can notice what changes occurred and try to guess why. So first what happened when the glue and water mixed? [Girls call out answers.] What happened the second time? [Allows time for girls to answer.] So, what did adding more borax do? how did it change the results? Did it make a difference to add the color later? [Takes a few moments to describe or draw what happened to the glue and borax to make slime.] Now, we're just about done here, but before we go, we all need to wash our hands because this slime will make you sick if you eat it. Also, if you decide to take it home, remember to keep it away from little kids and remind everyone that they absolutely cannot eat it!! Write 'Do Not Eat' on the bag, too! I hope you all had as much fun as I did today. And while I don't get to make slime every day, I do get to experiment with chemical reactions. And, as we discussed at the beginning, chemists try lots of different things. I hope you have learned what fun chemistry can be.