guilford journal of chemistry volume 1 (2007-2008)
DESCRIPTION
uilford journal of chemistry volume 1 (2007-2008)TRANSCRIPT
The
Guilford
Journal
Of
Chemistry
Volume 1 Number 1 October 19, 2007
This issue is dedicated to the investigation of the well-known Mentos Eruption.
Several discoveries are recorded for the first time in this issue, including:
Cold Mentos increase the height of a mentos eruption
A method for extremely long (1 minute) Mentos eruptions
A method for remote-controlled Mentos eruptions
A method for creating a “Mentos mist”
2
The Guilford Journal of Chemistry Dr. Harry Brielmann, Editor
The premier, state of the art venue for publication and broad dissemination of first-rate, fundamental research in
all of chemistry and Mentos Research.
Contributors to the Mentos & Diet Coke Experiment Effect of Surface Coatings:
Jennifer A Carly C
Different Carbonated Drinks and Mentos:
Zach B Ethan S
The Effect of Mentos Temperature:
Rachel C Emma S
Diameter of Nozzle Size:
Aaron D Travis D
The Effect of Diet Coke Temperature:
Justin H Delayed Reaction:
Stephanie M Mike M
Remote Control Eruption:
Paul Mulligan Jared Searles
Spray Effects and Nozzle Shapes:
Gabriella Necklas Kierstin Wall
Fruity vs. Minty:
Allessia Pascarella Johanna Penry
Nozzle Effects:
Taylor Smith Rosie Steffen
3
4
Introduction to this Issue
This first issue of the Guilford Journal of Chemistry includes groundbreaking discoveries in the field of
Mentos Eruptions.
In its simplest form, the Mentos eruption involves dropping Mentos candy into a soda (usually diet coke),
resulting in a foamy eruption, which can often be several meters in height.
The first widely viewed Mentos eruption occurred on September 14, 1999 on the David Letterman show,1
though earlier eruptions using other candies (with less spectacular results) had been used primarily by
teachers dating back to the 1980’s.2 In terms of scientiic research this field is still in its infancy, since
this area of research has almost no peer-reviewed published research results,3 although numerous
videos documenting riveting eruptions are available on the internet,4 and on commercial television.5
Several unverified explanations have been offered to explain the eruption6, usually focusing on the
physical shape of the mint (so-called nucleation sites), or on the various ingredients in the mint,
particularly gum arabic. It is important to note that none of these hypotheses have been scientifically
verified.
This journal represents the first attempts to scientifically investigate the mentos eruption. Several
previously unrepoted discoveries are documented in this journal.
Perhaps the most fascinating discovery was made by Cutler and Smith.7 This featured papers reveals
that that the height of a mentos eruption can be dramatically increased by freezing a mentos candy
prior to dropping it in the soda. Coupled with the predictable observation that heating a mentos candy
will increase the height of an eruption, this creates a bizarre result: the the height of a mentos eruption
is relatively high when the candy is cold, low when the candy is at room temperature, and then high again
when the candy is warm or hot. This discovery could in principle create world-record eruption heights
(the current record is 29.2 feet).
Another serendiptous discovery was made by Marsh and Moalli.8 While attempting to create a time-
delayed Mentos eruption, they chanced upon a method for sustaining an eruption for over 40 seconds.
More importantly, their graph suggests that this method could be applied to create eruptions that occur
for several minutes in theory, though there were some occasional reproducibility issues that will have to
be addressed.
Several of these papers are design-based, in which an eruption of a certain type is desired and executed.
Methods for creating several spectacular effects are published in this issue. Those interested in
creating a unique misting effect should read the work of Necklas and Wall.9 Those looking for both an
extremely high as well as a sustained eruption should turn to the work of Davis and Dillon.10
Space does not permit the higlighting of all articles. However, all of these investigations created
spectacular eruptions and we hope you enjoy reading about them
Dr. H. Brielmann
Editor in Chief
The Guilford Journal of Chemistry
5
References:
1. For an informative historical account of the Mentos Eruption, Speve Spanglers website is
recommended: (http://www.stevespanglerscience.com/experiment/00000109. Note that the original
Letterman Show Mentos Eruption may be viewed on the internet at
http://www.chem.uic.edu/marek/letterman0/video/mentos.htm.
2. For accounts of Mentos-like eruptions dating back to the 1980’s, see: Marek
http://www.rimmkaufman.com/rkgblog/2007/12/21/steve-spangler/
3. For example, the search term Mentos gives no results currently from polular scientific search
engines currently (2008), including PubMed or Google Scholar. Online material is available from
Scientific American (http://science-community.sciam.com/blog-entry/Sciam-Observations/Soda-
Fountains-Diet-Coke-Mentos/300004196) as well as detailed hypotheses by the Royal Society of
Chemistry (http://www.chemsoc.org/pdf/learnnet/classicdemos/mentosexplosion.pdf), but no
experiments were performed in either case to test their ideas.
4. In addition to YouTube, other websites have arrived that are dedicated to the mentos eruption. Of
particular mention is geysertube (http://www.geysertube.com/blog/), where one can view the Mentos
Eruption in ultra-slow motion.
5. For example, on the popular television series Mythbusters
(http://dsc.discovery.com/fansites/mythbusters/mythbusters.html).
6. Most literature on the Mentos Eruption cites the website of Fred Senese
(http://antoine.frostburg.edu/chem/senese/101/consumer/faq/mentos.shtml), however there are no
experiments performed or cited in support of these hypotheses.
7. Rachel Cutler and Emma Smith, Guilford Journal of Chemistry, Volume 1, Pages 6-12 (2007).
8. Steffi Marsh and Taylor Smith, Guilford Journal of Chemistry, Volume 1, Pages 13-16 (2007).
9. Gabriella Necklas and Kiersten Wall, Guilford Journal of Chemistry, Volume 1, Pages 33-35 (2007).
10. Aaron Davis and Travis Dillon, Guilford Journal of Chemistry, Volume 1, Pages 17-18 (2007).
6
Mentos Eruptions are increased by heating or Cooling the Mints. By Rachel Cutler and Emma Smith
Introduction:
Although there have been numerous experiments regarding the temperature of the soda versus
the height of the explosion; we have found that there are no apparent results of the effect of the
temperature of the Mentos in regards to the height of the explosion. 1Many people have conducted
these experiments because it is fun to watch, and because it is quite interesting as to what makes the
two create such a fantastic reaction. Most scientists say that it is the gum arabic that reacts with the
soda and produces the desired result2. There may have been experiments done regarding this, but we
have not found any results of those experiments. This had an effect on our experiment because we had
no previous results to compare our findings to. But in a way this was also good, because it was as if we
were the first ones who were discovering the effect temperature-changed Mentos had on Diet Pepsi.
The reaction between Coke and Mentos usually produces a good reaction3, and although our experiment
was modified it nonetheless produced good results.
Summary:
We wanted to see if the Temperature of the Mentos affected the height of the explosion when
dropped into a bottle of diet Pepsi. We froze Mentos, heated them up, and kept them at room
temperature to test the effects of each one, and then measured the height of the explosion of the diet
Coke.
Experimental Section:
Our goal was to find which temperature most affected the soda, and would therefore create the
biggest explosion. To do that we picked three different temperature areas to focus on: coldest, room
temperature, and the hottest. We put one package of Mentos in a freezer, another sitting out in the
room undisturbed, and another we wrapped in tinfoil and put on a hot plate. We then chose ten Mentos
and put them into a graduated cylinder on top of an open bottle of Pepsi. I walked away after I opened
the bottle of Pepsi, and Rachel ran away immediately after she dropped the Mentos into Coke. By doing
this I was able to get the first look at how the explosion went, and then both Rachel and I were able to
concentrate together once she ran away. We didn’t use any kind of nozzle because we were focusing on
finding how the temperature of the Mentos affects the height of the explosion. We considered our
negative control to be the neutral Mentos, which did produce a result, but not the one that we most
desired. Our positive controls were the Mentos we either heated or froze. Through this we were able to
compare the results of the positive controls to the results of our negative control. Overall, our
experiment was one based not on design, but rather upon finding an answer through an experiment that
produced results.
Experimental Procedure:
Materials:
~at least 3 bottle of Diet Pepsi
~at least 3 packages of Mentos
~2 meter- sticks
~a bin to catch all the sodas if you are conducting the experiment inside
1 http://chemistry.org/education/chemmatters.html
2 http://en. wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption#Explanation.
3 http://en.wikipedia.org/wiki/Mentos#Mentos_and_soft_drink_reaction
7
~towels to clean up the surrounding area, again if you are conducting the experiment inside
~tinfoil
~a hot plate
~a freezer
~a thermometer ~a graduated cylinder which you’ll put your Mentos in
Procedure:
1. Gather all the materials that is necessary for the experiment at hand
2. Put 10 Mentos in a piece of tinfoil in a freezer, and keep them there as long as possible. Put another 10
in another piece of tinfoil and put on the hot plate; remember to keep checking the Mentos so they don’t
melt, or worse, start a fire. And finally, keep another 10 Mentos out to absorb the surrounding
temperature.
3. Set up your experimentation area; with your soda in the bucket, and at least 2 meter sticks tied or
taped together and put the 10 Mentos in the graduated cylinder.
4. Have one person open the bottle of Coke, and the other person line the graduated cylinder up with the
opening of the bottle. After the person who opens the bottle up is done with their job they should move
in front of the area so they can see how high the explosion is. The other person should drop the Mentos
into the bottle and run away as fast as possible so they don’t get wet.
5. Continue the experiment with the other two packages of Mentos and soda bottles, and do as many
experiments as possible so as to increase the validity of your results. Record your results as you go along
in your experiment.
Conclusion:
Through this experiment we were able to realize and discover the fact the temperature of the
Mentos does have an effect upon the height of the explosion. The Mentos that were heated to a degree
of 313K reached a height of about two meters, or 200 centimeters. The Mentos that were kept at room
temperature were about 303K; reaching a height of about 30 centimeters. Our biggest explosion by far
was that produced by the Mentos that were frozen to a degree of 263K, and the force that the
explosion hit the towel with was so great that it sprayed outwards. Because of that, we can only roughly
judge that the explosion reached a height of 350 centimeters. Our results showed us that the
temperature of the Mentos really does have an effect on the height of the explosion.
Although our experiment did produce valid results there were a few errors along the way. Those
included not all the Mentos falling into the Pepsi, and therefore not producing the full effect. We were
also not completely exact in judging the height of the explosion, most of the time we had to make a quick
estimate of where the peak of the eruption was. To make our results more valid we should have done
more tests, which would have given us more support in the deduction that the more extreme the
temperature the greater the eruption will be and more validity regarded the results we made.
Overall, we were able to discover what we had initially wanted to find out; the temperature of the
Mentos does have an effect upon the height of the eruption of the soda. However, to make our results
more valid and better understood we should have done more tests; we also should have done more
experiments because not all of the Mentos were dropped into the Pepsi which made the eruption results
differ. However, we can concur that height is affected by temperature, and we are positive that if
future tests were done regarding this, the scientists or whoever is conducting the experiment will find
the same results that we found.
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0
50
100
150
200
250
300
350
He
igh
t o
f E
xp
lost
ion
(Ce
nti
me
ters
)
236K
303K
313K
Te
mp
era
ture
(K
elv
in)
Th
e E
ffe
cts
of
the
Dif
fere
nt
Te
mp
era
ture
s o
f M
en
tos in
Die
t C
oke
9
Sustained Mentos Eruptions. Creation of a 40 Second Mentos Eruption by Mike Moalli and Steffi Marsh
Summary
We tested coated mentos to see which coating would create the longest diet coke and mentos eruption.
After testing our control, oil, sugar, molasses, and honey, we concluded that honey made the longest
eruption of 40.28 seconds.
Introduction
There is little to no information about how to delay the mentos reaction or how to make a prolonged
mentos eruption. However it is believe that what causes the mentos and diet coke reaction is not a
chemical reaction but a physical one. The gellan gum and gum arabic in the mentos dissolve and breaks
the surface tension. This disturbs the water connection, so that it takes less work to expand and form
new bubbles¹. Each mentos candy has thousands of tiny pores all over its surface. These tiny pores
function as nucleation sites for carbon dioxide bubbles to form. When the mentos enter the soda,
bubbles form all over their surface. They quickly sink to the bottom, causing carbon dioxide to be
released by the carbonated liquid with which they come into contact along the way. The sudden increase
in pressure pushes liquid up and out of the bottle².
Experimental Section
Our original experiment was to design a delayed mentos eruption. In order to do this we decided to coat
the mentos in a variety of different substances to get the desired affect. Some of these substances
including: honey, oil, molasses, sugar, salt, and others. We would coat three mentos in each of the
substances and drop them into a small twelve ounce bottle of diet coke and then time how long the
reaction was delayed compared to the control (three mentos that were not covered in any substances).
After completing this we found that none of the substance had any significant delay in the reaction,
however we notice that different substances gave a longer reaction. Using this newfound data we
10
retested some of the substances and timed how long each reaction was. After completing this we found
that honey worked the best for creating a longer reaction.
Results
control 7.17
oil 7.89
sugar 10.32
molasses 30.18
honey 40.28
Conclusion
After conducting our experiments we have come to the conclusion that honey coated mentos work the
best for a prolonged mentos and diet coke reaction. However our original experiment was inconclusive in
finding a substance that delayed the mentos reaction. But in the progress of trying to find a substance
that would delay the mentos reaction we found that some substance prolonged the mentos reaction by as
much as 30 seconds. Some follow up experiment may include: the amount of honey used in covering the
mento, break down honey into pure substance and seeing which substance in the honey is the main
component in prolonging the reaction, and using different kinds of honey. Although we did not achieve
our intended goal of making a delayed mento reaction, we believe that we have found something more
useful and more fun overall.
Materials
1. 2 ounces of the following at room temperature:
a. Sugar
b. Molasses
c. Honey
d. Oil
e. Water
0
5
10
15
20
25
30
35
40
45
reaction time (in
seconds)
control oil sugar molasses honey
types of coatings
Effects of Coatings on Mentos
control
oil
sugar
molasses
honey
11
2. 5 pieces of string each about 15 centimeters long
3. 5 two liter bottles of diet coke
4. At least 50 regular mint mentos
5. Tongs
6. Drill (to make a holes through the mentos)
7. Pencil or pen and paper (to record results)
8. Stop watch
9. Towel
Experimental Procedure
1. Take all of the mentos and drill holes though them.
2. Put them in groups of ten and tie ten mentos on each of the five strings. Make sure they are tied close
together so there is room to hold the string before you drop it into the bottle.
3. Make sure to do this experiment outside where it’s okay to make a mess of diet coke and mentos.
4. The first test will be the control so there is no need to coat this sting of mentos in anything.
5. Have your stopwatch ready because the string of mentos needs to be dropped into the bottle as soon as
it is opened (to keep the carbon in) and the explosion will begin as soon as the string is dropped.
Remember, you are testing how long the entire explosion takes to compare it to the other coated
mentos.
6. Open the bottle of diet coke and immediately drop the string of mentos into it. Stand clear at least
three feet to prevent being soaked in diet coke.
7. Once the diet coke reaction has stopped fizzing out the top, record your results.
8. This time you’re going to be testing the honey. Dip the string of mentos into the honey and use the tongs
to make sure there’s a nice thick coat of honey each of the mentos. Make sure to use a new bottle of
diet coke and a new string of mentos each time you perform a trial because if either of them have been
used for a previous trial, there will be no diet coke eruption.
9. Now repeat steps 4-7 with molasses and then repeat the same steps with oil. Then skip to step 10.
10. When you’ve finished testing the control, honey, molasses, and oil, now test the sugar. Quickly dip your
last string of mentos into the water before you coat it in the sugar. Again, repeat steps 4-7 with the
sugar mentos, and then skip onto step 11.
11. Once all the experiments are completed, use the towel to clean up any mess if needed. Don’t forget to
recycle the diet coke bottles.
References
1. http://en.wikipedia.org/wiki/Diet_coke_and_mentos
2. http://www.stevespanglerscience.com/experiment/00000109
12
Remote Control Mentos Eruption by Paul Mulligan and Jared Searles Manuscript in preparation.
The Effect of Nozzle Size on the Height of Mentos Eruptions. Discovery of a method for thin, sustained eruptions
by Aaron Davis and Travis Dillon
The purpose of this experiment is to see if we use different nozzle sizes if it would affect the size of
the eruption of diet coke when mentos is put into it. We believed that the smaller nozzle size we used
the higher the eruption would go. When we conducted our experiment we were correct. When we placed
3 mentos into a 12 ounce diet coke bottle with no cap the eruption only went 8 centimeters high. Except
when we put 3 mentos into a 12 ounce diet coke bottle with a 3 millimeter nozzle that the eruption went
over 2 meters. We also tried with a nozzle size of 11 millimeters but the height of the eruption only
went 61 centimeters.
When we conducted studies on the height of diet coke eruptions when mentos is put into the coke we
found out that the smaller nozzle size the higher the eruption and the longer the eruption will last. With
a larger nozzle size the eruption will not go as high nor as will the eruption last as long.
In our experiment we conduct an experimental procedure that focused on how different nozzle sizes of
diet cokes will affect the size of eruption when mentos is put into the diet coke. We used 3 diet cokes
with no caps, 3 diet cokes with 3 millimeter nozzle, and 3 diet cokes with 11 millimeter nozzle. We placed
3 mentos in each diet coke and measure the height of the eruption using meter sticks.
In our experiment we found out that the smaller nozzle size the higher the eruption will go. We came to
this conclusion because when we used a nozzle size of 3 millimeters we got our highest eruption of over 2
meters. The average of the eruption with a 3 millimeter nozzle was over 2 meters. When we did not use
a cap at all the average height of the eruption was 6.7 centimeters, the lowest eruption we had. When
we used a middle size nozzle of 11 millimeters we got a larger eruption then using no cap but a smaller
eruption when we used a 3 millimeter nozzle.
Procedure:
1. Gather materials
2. Take 3 12 ounce bottles of diet coke and open cap
3. Place 3 mentos in each of the three bottles
4. Measure the height of the eruption by using a meter stick
5. Record the data you collected
6. Repeat step 2
7. Take a drill and drill a 11 millimeter hole into all three caps
8. Repeat steps 3, 4 and 5
9. Repeat step 2
10. Take a drill and drill a 3 millimeter hole into all three caps
11. Repeat steps 3,4, and 5
http://eepybird.com/science.html
http://eepybird.com/How%20To%20Do%20It%20Yourself!.pdf
13
14
Caps with 8mm holes.
Caps with 4mm holes.
NOZZLE DESIGNS CREATE SPRAY EFFECTS FOR MENTOS
ERUPTIONS Taylor Smith and Rosie Steffen
Introduction: “The Mentos and Diet Coke Experiment” is caused when Mentos mint candies are dropped
into a bottle of a carbonated substance. The result is a jet of soda which spews from the neck of the
bottle. The reaction is due to the rapid expanding of carbon dioxide bubbles on the surface of the
candy. i
Experiment: In order to create a Mentos eruption, one releases a number of Mentos mint candies into a
bottle of Diet Coke. When the two elements of the experiment combine, they result in an explosion
consisting of the carbon dioxide “fizz” of the Diet Coke. In this particular
experiment, holes of varying sizes and patterns were drilled into the caps of the
Diet Coke bottles prior to the release of the Mentos, thus causing the height and
spray patterns to also vary. To enhance the height of the results, the holes drilled
in the bottle caps must be smaller. When designing the experiment, drilling holes in
a circular formation, created a fountain effect with the “fizz,” or by arranging the
holes in a line formation, the “fizz” erupts in a similar fashion. In order to create a
more horizontal effect of the spray, the holes should be drilled at an angle,
pointing as much towards the opposite side of the bottle as possible. The holes
cannot be drilled on the side of the cap itself; because of they would directly
interfere with the cap’s ability to hold onto the bottle, thus resulting with
projectile qualities. In this particular experiment, the hole which created the highest and longest lasting
spray effect was a single hole in the center of the cap drilled with a 4mm drill bit.
Conclusion: In this experiment, the best results were the single, 4mm sized
hole because the carbonation was so concentrated to a single are and
therefore resulted in the highest height (6.09m or 20 ft.) and the hole
which was drilled at an 8mm resulted in
the lowest height (.9144m or 3ft.). This
experiment could be modified for
better results by applying further
variations to the nozzle designs to better
shape the eruption and thus increasing
the number of eruptions in order to achieve the desired effect.
15
Experiment Procedure: Gather materials: 1 two liter bottle of Diet Coke (otherwise unflavored for best results), 1
package of at least ten mint Mentos, 12 cm of dental floss (or other string), a 5 cm (at least) thick piece
of plywood, a 5cm roofing nail, a 4mm and 8mm drill bit, a power drill and two or three meter sticks.
Step 1: Using the roofing nail, score ten Mentos by slightly applying pressure to the middle of the
Mentos candy. Create a depression in the candy so that the drill bit will not slip off the Mentos when
drilling. Do this for all ten candies.
Step 2: Set up your drilling station by laying the plywood down. Ready your ten scored Mentos and
begin to drill through them. Start by applying slight pressure downward on the candy while slowly drilling
and only slightly increasing the drilling speed once the hard sugar coating is broken though. The speed
increase after the coating, is necessary because the inside of the candy is gummy and a faster speed is
needed to work through it. The candy might crack in half, do not use these because they could break
apart during the experiment and cause a premature eruption. Repeat this process for all ten Mentos.
Step 3: Drill the desired design in the bottle caps. It is better to collect other bottle caps and
drill those because if the caps are removed from the test bottles, the carbonation in the soda will
escape. Drill the desired designs in both diameters but on separate caps so that the height will vary.
Remember that fewer holes in the caps create a greater concentration and therefore create the best
results.
Step 4: String your Mentos on the dental floss. Once you have completed that, take the string
and thread it through one of the central holes in the drilled bottle caps.
Step 5: Stand the three meter sticks end to end, vertically. Secure them as you see fit (duct
tape is the best). Attach them to the Diet Coke bottle in the same fashion so that they will record the
height of the eruption.
Step 6: Open your test bottle and quickly remove enough soda so that when you screw on the
drilled cap, holding the string of Mentos, the soda will not touch the candy resulting in a premature
eruption. Once the drilled cap is securely on, hold the string of Mentos vertically and make sure it will
not get stuck anywhere on the cap when it is released.
Step 7: Before letting go of your sting, have a partner stand nearby to take pictures of the
eruptions because this is a more accurate method of recording the eruption height.
Step 8: Release your string and run!
(Repeat the procedure as many times as you wish, try varying the number of Mentos to achieve different heights.)
16
17
The Effect of Soda Type on the Height of Mentos
Eruptions By Ethan Shore and Zack Brown
Summary: We tested the effect of different soda types on the height of mentos based
eruptions in 2 liter soda bottles. We did 2 trials for each soda; Diet coke had explosions of .6 and 1.1m.
Coke explosions of .1 and .15m . Sprite had explosions of .45 and .57m. Sprite zero had explosions of 1.1
and .95m. Sprite zero had the highest average explosion, with an average of 1.025m.
Introduction:
While many people have tried the Diet Coke and Mentos eruption experiment
before, not many people have attempted to test different soda types with Mentos. However, the
phenomenon was started by Steve Spangler, a science teacher, which got an explosion with Diet Coke and
Mentos reaching 5.5 meters¹. He determined that as the rather heavy candy falls to the bottom of the
bottle, carbon dioxide is released and the suddenly increased pressure pushes the liquid out of the
bottle¹. One science class also attempted testing 44 different soda types on Mentos eruptions².
Experimental:
We tested each soda by opening the each bottle of soda, and then placing 5 Mentos inside
the soda bottle, and then waited for the eruption. There were meter sticks behind the soda, so we could
measure each eruption. We used 5 Mentos for each trial.
Results:
Conclusion:
Based on our results, Sprite Zero causes the highest Mentos eruption with an
average eruption of 1.025m. Diet Coke had the second largest explosion with an average of .85m. Sprite
had the 3rd largest explosion, with an average of .51m. And Coke had the smallest average explosion, with
an average of .125m.
The Effect of Mentos on Different Soda
0
20
40
60
80
100
120
Diet
Coke
Coke Sprite
Zero
Sprite
Soda
Heig
ht
Trial 1
Trial 2
18
This data was not 100% conclusive. During some of our trials, it was not clear whether all 5
Mentos made it into the bottle before the explosion occurred. Another factor lessening the
conclusiveness of the results is the fact that after we dropped the Mentos in, we had to move out of the
way very quickly. Sometimes, my hand partially hit an explosion, perhaps causing the height to drop. The
results of this experiment were somewhat valid.
Experimental Procedure
Step 1: Gather 2, 2 liter bottles of Sprite, Diet Coke, Coke, and Sprite Zero.
Step 2: Gather 40 Mentos, and a test tube (small enough for Mentos to fit in, large enough for
them to fall out).
Step 3: Take the plastic bin from the front of Dr. B’s room, and place it at one of the back
tables.
Step 4: Tie 2 meters sticks together behind it, making sure that the sticks are straight.
Step 5: Place a bottle of Diet Coke in the bin.
Step 6: Place 5 Mentos in the test tube.
Step 7: Open the bottle.
Step 8: Drop the Mentos in the bottle.
Step 9: Record the height of the explosion in your data.
Step 10: Repeat steps 5-10 for Diet Coke once more, and each other soda twice more.
References:
¹http://sciencecentered.blogspot.com/2007/04/mentos-and-diet-coke-geysir.html
²http://www.geysertube.com/blog/
19
How the Coatings of Mentos affects the size of the Mentos Eruption by Carly Clark and Jenn Agamie
Introduction: For our experiment we decided to test the different effects of mentos coatings on diet
coke to see the different heights of eruptions. To test our theory we used a control, which was the
regularly coated mentos, mentos without any coating, and mentos drenched in dish soap. After three
trials we were able to clearly see that the regularly coated mentos had the best eruption by far.
Summary: Throughout our experiment we concluded that the non-coated mentos had the worst height.
The average height in centimeters after three trials was only 33.33 cm. This shows that there was
hardly any eruption at all. The mentos soaked in dish soap averaged to be 58.33 cm, which is better than
the non-coated but still not superb. Finally, we were able to test the regular mentos and received an
average height of 230 cm. We made sure to use exactly ten mentos per liter of diet coke so that we had
a constant throughout our experiment.
Experimental Section: The design of our experiment was to see what actually made the mentos in the
diet coke to erupt. After several ideas were tossed around we decided to see if the coating had anything
to do with the eruptions. In order to test this idea we de-coated ten mentos and covered ten more in
Dial dish soap. Then we gathered ten more mentos and left them with their regular coating. Instead of
stringing the mentos onto a wire and dropping them into the diet coke bottles we decided to place all ten
of them into a graduated cylinder and hold a thin piece of paper over the opening. We flipped the
graduated cylinder upside down so that the opening covered with paper was lined up to the top of the
diet coke bottle. We tried to let as little carbonation out of the bottle as possible, so that there was
more of a reaction.
Procedure:
1. First, we gathered our materials, which consisted of a graduated cylinder, 3 liters of diet coke, and 2
packages of mentos. We also used dial dish soap, a beaker, and thin pieces of paper, two-meter sticks,
and a bucket.
2. Then we made three piles of ten mentos. One set we covered in soap, then next set was regular, and
the third we soaked in a beaker full of hot water so that the coating would dissolve.
3. After the mentos were ready, we placed one liter of diet coke in the bucket so that when the eruption
occurred soda wasn’t sprayed everywhere.
4. Next, we taped two-meter sticks together and tied them around the diet coke bottle so that we were
able to see the height of the eruption.
5. Then one of us held the graduated cylinder upside down above the top of the bottle. While the other
person unscrewed the cap.
6. As soon as the cap was unscrewed the person holding the graduated cylinder moved the paper and
released the mentos into the diet coke.
7. We made sure to stand far enough from the eruption so that we wouldn’t get soaked in soda, but close
enough to see the height of the eruption.
8. Once each different type of mentos underwent the experiment we recorded our data into a table.
9. We performed the experiment two more times. Each time recording our data to make sure the height
was accurate. We then averaged the height of the different mentos to see the results as one.
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10. Once each trial was through, we cleaned our station and compared our results to our hypothesis.
Conclusion: After having tested our experiment many times we came to a conclusion that the mentos
with the regular coating had by far the best eruption. While it averaged in 230 cm the other two only
went up to 58.33cm (soap), and 33.33 cm (non-coated). As we thought, there is something in the coating
of the mentos that effects the eruption. During our experiment we were very much in awe to see that
the two mentos that were changed had such a low height.
References: 1.”Mentos Geyser.” Making Science Fun. Feb.10, 2008.
http://www.stevespanglerscience.com/experiment00000109.
2. “Diet Coke and Mentos Eruption.” Wikipedia, the Free Encyclopedia.Feb. 10,2008
http://en.wikipedia.org/wiki/Mentos-eruption.
3. ‘How to Make a Soda Bottle Volcano.” Extreme Diet Coke and Mentos Experiment, Wikihow. Feb.11,
2008
http://www.wikihow.com/make-a-soda-bottle-volcano.
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Different Coatings
The Effects of Different Mentos Coatings in Diet Coke
Series1
Series2
Series3
21
Warm Soda has a dramatic effect on the Height of a Mentos Eruption
by Justin Husted
While numerous experiments have been done with the coke mentos eruption, sometimes called the
coke mentos geyser or rocket, very few have tried testing the effects of the temperature of soda
before adding the mentos. Some brave experimenters have come to the conclusion that the reaction
rate appears to double for every 10 degrees Celsius that you heat the diet coke. Similarly for every 10
degrees that the soda is cooled (or frozen) the reaction power and height is cut in half. 4 Also according
to www.stevespangler- science.com, the temperature of the soda greatly affects how much force and
height the geyser of soda fizz will shoot up to.5 My goal is to duplicate their experiments in an attempt
to find if the temperature of the diet coke actually affects the height of the mentos eruption.
The Experiment:
By submerging bottles of coke into different water temperatures, we can safely control the
temperature of the soda inside. The three temperatures being used in this experiment are cold, (262 K)
room temperature (298 K) and warm diet coke (approximately 308 degrees K). Using eight mentos in
each bottle, they will be set up to erupt and see which yields the biggest eruption.
Summary of findings:
The results of the experiment were clear and as expected. The coldest coda resulted in the small
and shortest eruption of diet coke. The room temperature soda had expected results and was a relative
increase from the cool soda. The warm diet coke’s results sky-rocketed. Of the two warm test trials,
both blast the coke into the air with a large amount of force, resulting in an average height more than
double what the room temperature soda achieved.
Conclusion:
At the conclusion of this experiment I found that, as expected, the warmest soda temperature
produced the biggest results of the three. The coldest soda temperature barely erupted out of the
bottle. The cold soda was submerged in water measured at 263 degrees Kelvin. After putting in eight
mentos, the following eruption resulted in about 20 centimeters of height. The next largest was the
soda that was left in the classroom for two days to ensure it was the average temperature of the room.
The temperature was measured at 298 degrees Kelvin. The resulting eruption was approximately one
meter exactly. (100 centimeters). The final trial was of the warmest soda was that which was heated in
water measured at 308 degrees Kelvin. The resulting reaction resulted in an eruption of 300 centimeters
(three meters). By the results of the data, it is easily safe to conclude that the warmer the diet coke
temperature, the more height the eruption gained.
Experimental Procedure:
The following steps will lead to the exact duplicate of the above experiment.
4 Username: “Labmonkey” Yahooanswers.com January 10
th, 2008
5 www.stevespanglerscience.com, mentos and soda temperature.
22
1) Obtain materials, needed is: three 2 liter bottles of diet coke, exactly 24 mentos candies, a
thermometer, meter sticks, and glass cylinder containers to house hot and cold water.
2) Submerge one sealed bottle of diet coke into a cylinder of cold water, measured at 262 degrees Kelvin.
Leave in for at least ten-twenty minutes.
3) Submerge a second bottle into warm water. Use the thermometer to measure the temperature of the
water to 308 degrees Kelvin. Leave in for ten-twenty minutes.
4) The third and final bottle should be left in normal room temperature conditions (approx. 298 degrees
Kelvin)
5) Set up a measuring system of at least two meters sticks in a container to catch the spraying coke. Tape
or string should be used to attach two sticks together.
6) Using a graduated cylinder to house eight mentos, un-attach cap of the first bottle and drop mentos
inside, stand back, observe and measure height using meter sticks.
7) Repeat step six for the remaining two bottles of diet coke. Use exactly eight mentos each time and
record each height in a table for future reference.
8) Graph and conclude data.
23
Creating a “Misting Mentos Eruption”
By Gabriella Necklas and Kiersten Wall
Summary: For our experiment we tested how the shape of the opening that the soda sprays through
affects the height of the geyser. Our goal was to determine which nozzle created the greatest height.
From our experiment we were able to conclude that the smaller the hole the higher the geyser created.
We were also able to see that a circular shape works better than a slit in the cap does.
Introduction: In the field of Mentos eruptions there is still some debate over how the reaction occurs.
However, there is one relatively accepted reason for the reaction. “When you drop the Mentos into the
soda, the gelatin and gum arabic from the dissolving candy break the surface tension. This disrupts the
water mesh, so that it takes less work to expand and form new bubbles. Each Mentos candy has
thousands of tiny pits all over the surface. These tiny pits are called nucleation sites - perfect places
for carbon dioxide bubbles to form. As soon as the Mentos hit the soda, bubbles form all over the
surface of the candy.” ii It is also well noted that a substance under pressure that is forced through a
small hole will go higher than the same substance through a substantially larger hole. This is how we
came to the hypothesis that our small hole would produce the largest geyser.
Experimental Section: For our experiment we conducted two trials. Each trial followed the same
procedure, our goal was to try and get the most accurate results possible. We dilled a hole into the
center of each mento and then strung 10 mentos for each nozzle type. We then pulled the other end of
the string through the nozzle so that the mentos would hang below the nozzle and into the bottle while
we had about a two inch portion of string to hold onto until the designated time for eruption. We also
attached two meters end to end and staked them into the ground behind our soda bottles in order to
measure our eruptions. Once all of these preliminary steps were taken care of we screwed on the nozzle
that was being tested and let go of the string in order to release the mentos into the Diet Coke.
Results Section:
24
Nozzle Type Trial 1 Trial 2
Control 1 meter 1.2 meters
Small Hole .7 meters About 3.5 meters *
Straw .5 meters 2 meters
Small Slit .2 meters 1.5 meters
Measurements have been rounded. *Our measuring device only went up to two meters, for this
measurement we had to estimate its final height.
Our first trial is significantly different than our second trial for all of our experimental nozzles because
of a malfunction we had with our release cord. For our second trial we were able to fix the problem and
our results are much larger because of it.
Conclusion: Our results conclusivly show that the small hole is the optimum nozzle size to produce a
large geyser. The small hole went 1.5 meters higher than its closest rival, the straw. Even though the
straw and the small hole’s openings had the same diameter they both had drastically different results,
we believe that the length of the straw affected the height of the geyser. Also while the small slit did
manage to go higher than the control, by only .3 meters, we were able to see that at a certain point the
hole becomes too small for the geyser and it has the affect of creating a much shorter eruption. We
noticed during our trial of the small slit that more of the soda was coming out in a mist like fashion
creating a much shorter and less impressive eruption. For follow up experiments it would be a good idea
to try nozzles of different lengths. For instance cutting a straw into three different lengths in order to
see if it was really the length of the straw that caused it to create a shorter geyser than the small hole.
Another possible follow up experiment would be to have holes that gradually increase in diameter to
check if the small slit really was too small and if the small hole really is the optimum size.
Procedure:
1. Gather 8 two liter bottles of Diet Coke, 4 boxes of Mentos, string, a drill, a straw, and a pastry nozzle
used to make ribbon like lines.
2. Drill a ¼ inch hole into a soda cap, this will be the small hole nozzle.
3. Drill another ¼ inch hole into another soda cap and insert the straw into the hole so that when the cap is
screwed onto the bottle the strawl will stick up on the outside. This will be the straw nozzle
4. Now drill a hole into another cap that is large enough to fit the pastry nozzle. Then insert the pastry
nozzle into the hole so that when the cap is screwed onto the bottle the nozzle is on the outside. Hot
glue the pastry nozzle into place so that no liquid can escape. This will be the small slit nozzle
5. Now drill a hole into the center of 80 Mentos, this will be enough for both trials on each nozzle.
6. Tape two meter sticks end to end and stake them into the ground so as to measure the eruptions.
7. Place an open Diet Coke infront of the meter sticks.
8. String 10 drilled Mentos and hold them so that only the bottom two Mentos are in the neck of the
bottle. Count down from three and drop the Mentos into the soda. Record the eruption, this will be your
control.
9. Repeat step 8 for the second trial of the control.
10. Now string another 10 Mentos. Run the top of the string through the small hole and screw the small hole
nozzle with the mentos dangling beneath it onto a new Diet Coke bottle, make sure that the Mentos will
not touch the diet coke, you may need to pour out some soda. Place the ready bottle infront of the
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meter sticks and count down from three then drop the Mentos into the soda and record the
eruption.This will be your small hole trial.
11. Repeat step 10 for the second trial of the small hole.
12. Now string another 10 Mentos and run the top of that string through the straw nozzle. Screw the nozzle
onto a new Diet Coke bottle so that the mentos hang below it, make sure they do not touch the soda, you
may need to pour some soda out. Place the readied bottle infront of the meter sticks and count down
from three, then drop the mentos into the soda and record the height. This will be your straw trial
13. Repeat step 12 for trial two of the straw nozzle.
14. String another 10 Mentos and run the top of the string through the small slit nozzle. Screw the small
slit nozzle onto a new bottle of Diet Coke so that the mentos hang inside the bottle, make sure they do
not touch the soda, you may need to pour some soda out. Place the bottle infront of the meter sticks,
count down from three and let the Mentos fall into the soda. Record the geyser, this will be your small
slit nozzle trial
15. Repeat step 14 for trial two of the small slit.
16. Clean up the workspace.
Gabriella Necklas and Kierstin Wall
i “Diet Coke and Mentos Eruption,” http://en.wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption
ii http://www.stevespanglerscience.com/experiment/00000109