By Golly, By Gum, By Time

Summative Lab Assessment

Objective:

The purpose of this lab activity is to learn how to conduct a lab experiment. When you have completed the lab, you will be able to conclude how the time a piece of gum is chewed affects its mass.

Safety:

Never put your gum directly on the scale. Use a piece of parchment paper and correctly tare your balance each time. Take your parchment paper with you.

How does the amount of time gum is chewed affect its mass?

Hypothesis:

I think ____________________________________________________________________________

____________________________________________________________________________Because_____________________________________________________________________

____________________________________________________________________________

Materials:

Balance

Gum

2X2 parchment paper

Timer

Directions

1.  Select a piece of gum.
2. Cut a 2x2 inch piece of parchment paper.
3. Write your name (initials) on the parchment paper.
4. Using a balance, find the mass of the gum (do not chew it yet).
5. Record this mass in the data table.
6. Chew the gum for two minutes.
7. Place the gum on parchment paper and find the mass of the chewed gum.
8. Repeat this process four more times to complete every space in the data table.

Data:

Questions:

1. Was your hypothesis correct? Why or why not?

2. What does your data tell you and is this data reliable? Why or why not?

3. What is an example of a control we used in this experiment?

4. What was the independent variable from this experiment?

5. What was the dependent variable from this experiment?

6. What could be an example of bias from this experiment?

7. What would the next steps be for a scientist performing a lab like this one?

Construct a graph below based on the mean class data from the By Golly By Gum lab

Be sure to include a label for your X and Y-axis including units, and a Title on your graph.

After completing the By Golly, By Gum experiment, Carlos decides to re-do the same experiment at home. He takes out a piece of gum, finds its original mass, and then begins chewing. After two minutes, he takes it out and find the mass again. He repeats this two more times. By this time, Carlos is really thirsty. He slurps down a milkshake and finishes the experiment. After graphing and analyzing his data, he concludes that the mass of the gum increased over time.

1. Does Carlos’s conclusion match what you see in your graph above? Why or why not?

1. Do you agree with Carlos’s conclusion? Why or why not? If not, give an explanation for his results.

Write two good scientific questions that you could ask after completing the By Golly By Gum experiment yesterday. Think about what a good next step or follow up question could be.

Question #1:

Question #2: