Running head: MIDTERM ASSESSMENT
Midterm Assessment
Ashley Miller
Ivy Tech Community College
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MIDTERM ASSESSMENT
Question #1: What will happen to a 9-inch balloon when ½ tablet of effervescent
antacid weighing 1.6g is added to graduated cylinder with 20mL of room temperature
(72.6 degrees) water?
Claim: The balloon will inflate to approximately 2 inches.
Procedure:
1. Gather all necessary material: three 9-inch (22.86cm) helium quality
balloons, one graduated cylinder, access to city water, and three packages of
effervescent tablets containing two tablets per package.
2. Open effervescent package and take one tablet out. Cut tablet in half, and
weigh the tablet so it equals 1.6g, on an electric scale.
3. Add 20mL of city water to a graduated cylinder. Wait and measure the
temperature of the water so it reads 72.6 degrees Fahrenheit.
4. Place the 1.6g tablet inside of the balloon.
5. Aggressively crush tablet on a solid surface 13 times until the tablet is
completely broken up inside the balloon.
6. Place the balloon around the top of the graduated cylinder. The balloon
should be 1cm below the rim of the cylinder.
7. Tip balloon 180 degrees so it is directly above the opening of the cylinder.
The tablet should fall and mix with the water immediately.
8. Time the balloon for one minute with a stopwatch.
9. Record the diameter of the balloon at its widest point horizontally.
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MIDTERM ASSESSMENT
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Evidence:
Trial
Ending Temperature
Diameter (inches)
1
76.2 degrees
2.75
2
73.7 degrees
1.5
3
76.2 degrees
1
Average
75.4 degrees
1.75
Research:
According to American Chemical Society, the antacid is an acid and the water is
the base. When the two interact with one another, the tablet dissolves in the water and
they produce carbon dioxide gas, which in turn blows up the balloon (American
Chemical Society, 2008). As you can tell in this experiment, we used only half of the
tablet and only 20mL of water. There wasn’t much of a reaction in any of the three trials
we tested. Had we turned the cylinder and dumped the contents into the balloon, we may
have had a better temperature reading after the two mixed together for the time allotted.
As a side note on the website, American Chemical Society states that the tested
balloon should be tossed after one use; unfortunately, our group continued to use the
same balloon for three trials each. They also made a good point to blow up the balloon a
couple times before the experiment before mixing the ingredients so the balloon can
expand easier (American Chemical Society, 2008).
MIDTERM ASSESSMENT
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Question #2: How does 40mL of city water at room temperature (72.6 degrees
Fahrenheit) change the inflation or expansion of the balloon when1.6g of an effervescent
antacid tablet is added?
Claim: The balloon will expand more than in the first trial.
Procedure:
1. Use a balloon not previously used in first trial.
2. Open an effervescent package and take one tablet out. Cut tablet in half, and
weigh the tablet so it equals 1.6g, on an electric scale.
3. Add 40mL of city water to a graduated cylinder. Wait and measure the
temperature of the water so it reads 72.6 degrees Fahrenheit.
4. Place the 1.6g tablet inside of the balloon.
5. Aggressively crush tablet on a solid surface 13 times until the tablet is
completely broken up inside the balloon.
6. Place the balloon around the top of the graduated cylinder. The balloon
should be 1cm below the rim of the cylinder.
7. Tip balloon 180 degrees so it is directly above the opening of the cylinder.
The tablet should fall and mix with the water immediately.
8. Time the balloon for one minute with a stopwatch.
9. Record the diameter of the balloon at its widest point horizontally.
MIDTERM ASSESSMENT
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Evidence:
Trial
Ending Temperature
Diameter (inches)
1
75 degrees
2.50
2
74.3 degrees
2.75
3
73.4 degrees
2.875
Average
74.2 degrees
2.71
Research:
In this experiment, we wanted to change the amount of water to see if that had
any affect while keeping the tablet still at 1.6g, or half a tablet. After reading an
experiment done by Rozeanna Steckler, Ph.D, it doesn’t necessarily matter, but the
temperature of the water maters. If the temperature of the water is hotter, the ingredients
react quicker and dissolve much faster, while the room temperature and even cold water
takes much longer too see the balloon expand (Steckler, Ph.D, 2005). I think that our
problem was we didn’t change the temperature; we just changed the amount of water.
Given the circumstance, we couldn’t get hot enough water without taking a bunch
of time away from the experiment; therefore, we just changed the amount to double what
we originally started with. We did notice that there were more bubbles the more the
crushed tablets were. This is believed to be because the surface area is smaller and more
easily dissolvable (American Chemical Society, 2008).
Question #3: How is the balloon affected when a whole tablet of effervescent is added to
20mL of city water at room temperature (72.6 degrees)?
MIDTERM ASSESSMENT
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Claim: The balloon will inflate more than previous trials.
Procedure:
1. Use a balloon not previously used in first two trials.
2. Open an effervescent package and take one tablet out. Measure the whole
tablet – it should read 3.3g on an electric scale.
3. Add 20mL of city water to a graduated cylinder. Wait and measure the
temperature of the water so it reads 72.6 degrees Fahrenheit.
4. Place the 3.3g tablet inside of the balloon.
5. Aggressively crush tablet on a solid surface 13 times until the tablet is
completely broken up inside the balloon.
6. Place the balloon around the top of the graduated cylinder. The balloon
should be 1cm below the rim of the cylinder.
7. Tip balloon 180 degrees so it is directly above the opening of the cylinder.
The tablet should fall and mix with the water immediately.
8. Time the balloon for one minute with a stopwatch.
9. Record the diameter of the balloon at its widest point horizontally.
Evidence:
Trial
Ending Temperature
Diameter (inches)
1
71.0 degrees
4.5
2
68.7 degrees
3.5
3
69.0 degrees
2
Average
69.6 degrees
3.33
MIDTERM ASSESSMENT
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Observation:

The balloon inflated quicker

Bubbles went all the way to the top of the cylinder

More bubbles were present
Research:
In this experiment, we used the whole effervescent tablet in 20mL of city water.
This is the most reaction we received in our three rounds. We believe this is to be
because there is more of a tablet to be dissolved in the water and will create more CO2 to
inflate the balloon. According to Iceberg Labs, the reason for this is because reaction is
an autocatalytic reaction catalyzed by the presence of water and heat, that generates CO2
in solution: HCO3- (+) H+ -----> CO2 + H2O (Iceberg Laboratories Products, 2009). My
group and I didn’t have very much time to see the tablets dissolve completely, but we
timed them to what we thought was the widest the balloon got within our window.
According to Iceberg Labs, the solution of the effervescent tablet contains a
balanced ratio of acids and carbonates; this balance is called a buffer. Additionally, with
effervescent tablets dissolved in liquid, the ingredients are absorbed quickly, completely
and uniformly (Iceberg Laboratories Products, 2009). As I stated before, we didn’t have
enough time to watch the tablet completely dissolve in any trial.
So basically what I’ve learned from this experiment is that the effervescent tablet
when mixed with water creates CO2, which builds enough pressure in the cylinder to
blow up the balloon; the warmer the temperature, the faster the balloon gets blown up. If
I had to do this experiment again, I would most definitely use warmer water to see those
results.
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Works Cited
American Chemical Society. (2008). It's a gas!. Retrieved from
http://portal.acs.org/portal/PublicWebSite/education/whatischemistry/scienceforki
ds/chemicalphysicalchange/chemicalreactions/CSTA_014883
Iceberg Laboratories Products. (2012). Effervescent technology overview. Retrieved from
http://www.iceberglabs.net/effervescent-chemical-overview.htm
Steckler, Ph.D, R. (2005). Physical science - speed up the fizz. Retrieved from
http://education.nacse.org/Curriculum/physical_fizz.html