Chewing on Chemistry & Bubble Gum Lab! Problem: What do you think is going to happen to the appearance, volume, mass, and density of a sample of bubble gum, if it is chewed for 10 minutes? Background: Read the following to learn about the history of gum. After reading, summarize the information in a short paragraph. Archaeologists have found 2,000 year old chewing gum in Sweden. The ancient Greeks and Mayans chewed various kinds of tree gums. So did the Pilgrims. They picked up the habit from the Native American Indians. The chewing gum we love today can trace its roots (sort of) back to the Battle of the Alamo in 1836! The leader of the Mexican army that overran the Alamo, while the likes of Davy Crockett and Jim Bowie died defending the fort, was General Santa Anna. Everyone knows that part of the story. What is not generally known is that a few years after the war, Santa Anna had left the military and gone into the tree sap business. He was in New York trying to interest American businessmen in buying sapodilla tree sap (an American tropical evergreen tree) from him and then finding a way to refine it into a cheap substitute for rubber! One of the men Santa Anna approached was a New Jersey inventor called Thomas Adams. Adams experimented with the sap, also known as chicle (as in Chiclets!), for some time before giving up in frustration and throwing the stuff out. That might have been the end of the story, however, Adams had a young son who, according to the legend, got in the trash and starting gnawing on the stuff. When Adams discovered his son happily chomping away, he got a great idea! Instead of chewing whale blubber (yummy!) or wax, Adams envisioned a nation chewing Santa Anna’s chicle. Within a year, “Adams New York Snapping and Stretching Gum” was on the market and selling like crazy – especially after it was flavored with sarsaparilla (what folks drank before there was Diet Pepsi). In 1928, Walter Diemer, a Philadelphia accountant, invented bubble gum. Today, the chicle has been replaced by sweetened, flavored, food-grade plastic. That is why, if you swallow your gum, it eventually passes out unchanged out of the body. If you are caught chewing gum in Singapore, you will be fined. If you are caught chewing gum obnoxiously in Fresno, you will be jailed. You will add to the colorful history today as you experiment with bubble gum in the laboratory. Summary: ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ Hypothesis: What do you think is going to happen to the appearance, volume, mass, and density of gum after you chew it? BE CAREFUL – EACH PERSON IN YOUR GROUP HAS A DIFFERENT PIECE OF GUM! Here is a sample hypothesis: The appearance of the gum will change from a nicely shaped piece of gum to a teeth-marked piece of gum. The mass will increase due to my saliva on the gum. This increase in mass will increase the density of the gum. There will be no change in volume. Make sure you phrase it as a testable statement. Think carefully about this – you will be graded on the quality of your hypothesis! ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ Materials: Make a list of the materials you are using in this lab. ____________________________ ___________________________ ____________________________ ___________________________ ____________________________ ___________________________ ____________________________ ___________________________ Procedure: 1. BEFORE CHEWING GUM: Measure all of the characteristics as follows, and record them in your data table 1 below. a. Appearance - write as detailed of a description as possible (texture, color, shape, etc.). b. Mass- use balance. c. Volume- Write down the length, width, and height of your bubble gum below. Calculate the volume of your gum in cm3 using the formula – use cm for your length, width , and height: Volume = length x width x height d. Density- calculate the density in g using the formula: Density = mass cm3 volume 2. Chew gum for 10 minutes. (No bubble blowing). 3. AFTER CHEWING GUM: Measure all characteristics as you did before chewing gum, and record in data table 1 below. a. Appearance- same as above. b. Mass- same as above. c. Volume- measure volume using your wrapper and a scale, since the gum is now shaped weird! Record the initial and final weights of the wrapper below, and then subtract the two to get the volume of the gum. d. Density- same as above. Data: MAKE SURE YOUR DATA HAS UNITS! Type of Gum: _________________________________________ DATA TABLE 1 Characteristic Before Chewing After Chewing Appearance Mass Volume = _______x ________ x ________ Wrapper weight: Final weight : Volume of gum : Density = m _ Volume Data Table 2 Individual in Group Type of Gum % Mass Change Calculations: Calculate the % change in mass BELOW as a result of chewing the gum. % Mass change = (mass after - mass before) x 100%. mass before Graphs: Make TWO BAR GRAPHS – one for mass and one for volume comparing the data from before and after chewing, using graph paper. Be sure to label your axes properly, title your graph, and use the correct units. ATTACH YOUR GRAPHS TO THIS LAB. YOUR GRAPHS WILL BE DIFFERENT FROM THE REST OF YOUR GROUP! FOR EXAMPLE: Mass is x-axis Time is y-axis Use color coded key to represent brand and flavor.