DETERMING THE HEATING RATE OF A LAVA LAMP
Jessica J
Cary Academy
ABSTRACT
The purpose of this experiment is to determine the heating rate of a lava lamp. It was
hypothesized that in one minute the temperature will increase about half of a degree.
This was proved incorrect; because it turns out that the temperature actually increases
less than half of a degree Celsius per minute. It was about one fourth of a degree
increase per minute. This is how the experiment was performed. The first lava lamp was
turned on. The temperature was measured with the temperature scanner; against the
outside of the lava lamp, after it has completely heated up for four hours. Next the
second lava lamp was turned on. The temperature was measured, again with the
temperature scanner outside of the lava lamp, also after it has completely heated up for
four hours. The temperatures of each were also measured at 100 minutes and 0
minutes, adding to the measuring at 245 minutes. Also, multiple experiments were
performed after this to make further investigations. Lava lamps that are different shapes
were compared. Homemade lava lamps were creating; determine if the temperature
affects how well it works. Also, different types of candy were dropped into the
homemade lava lamps to see if it caused a functional reaction. At the end of the first
experiment it was discovered that in one minute the temperature increases less than
half of a degree.
INTRODUCTION
The purpose of this experiment is to discover the heating rate of a lava lamp. The
outcome of this experiment was predicted. The hypothesis is that in one minute the
temperature will increase by about half of a degree. This was inferred, because it was
observed that when the lava lamp was turned off it was 23.3 degrees Celsius, and when
it was on it increases to 55. That means the heat increased 31.7 degrees in about three
hours (an average of how long it takes for a lava lamp to heat up completely). When
dividing the amount of minutes in those hours by the amount of degrees increased, an
approximate guess will be found.
Observations were taken on the lava lamps they were turned on and turned off. While
the lamp was off, the cold, hard wax was sitting at the bottom of the lamp in a pile. The
outside of the lava lamp felt cold; and both the water and wax were still. Though when
the lamp was completed heated, the wax looked very thin and more of a liquid than a
solid. It floated around that lamp slowly. The outside of the lamp felt hot. Quantitative
observations were also taken. The top surface of the lava lamp is 3 cm in diameter, and
the bottom surface of the lava lamp is 9 cm in diameter. The mass of the lava lamp
when it is turned off is 1,110 grams. The mass of the lava lamp when it is on is also 1,
110 grams. Also, the lava lamp is around 20 degrees Celsius when it is turned off. It
increases to 55 degrees Celsius when it is completely heated up. There were two lava
lamps observed and they were very different when turned on. Lava lamp #1 was 60
degrees Celsius and the blobs moved very quickly around the lamp. Lamp #2 was 50
degrees Celsius and the blobs moved very slowly around the lamp. This may be either
because of the light bulb wattage or how often the lamp is used.
The lava lamp uses the process of density to allow the blobs to move around the lamp.
Actually, this seems like a very simple method that Edward Craven-Walker discovered,
in 1963. When the lava lamps were first created, he called them the Astro Lamps. They
can be called many different things; lava lamps, Astro lamps and lava lamps. The blobs
inside of these lamps are made of vibrantly colored wax. The fact that they are wax
helps the procedure of density work very efficiently. When the lava lamps are turned off,
the wax is hardened and cold. It sits at the bottom of the lamp. Though when the lamp is
turned on the wax slowly begins to heat up. The light bulb sits at the bottom of the lamp,
and it warms the hard wax. As the wax becomes warmer and more of a liquid than a
solid, it also becomes less dense. This is where the slow process begins. Being less
dense, the blobs rise up to the top of the lava lamp; creating the beautiful patterns that
the lamps are known for. Once the blobs reach the top, they are not accessing the
same amount of heat; therefore; becoming more dense. The blobs slowly float down to
the bottom, and once they reach the warm light; lose density again. This is the very
never-ending process that creates the lava lamp.
Density is used to determine the thickness of a mass. Masses that are more dense
have less air inside of them, and masses that are less dense have lots of hollow space
in them. Everywhere; the density of an object stays exactly the same. Here’s an
example; ice floats in water. Well, that is because they are less dense than the actual
water. Since ice is frozen and packed in, it takes up a lot less space than water and it’s
also smaller. That makes the water denser; since it takes up a majority of a glass. That
is why ice floats in water; density. Density helps to find out whether objects will float or
not, just like with the ice floating in water. Also, helium balloons float in the sky because
they are less dense than the sky; for the same reasons.
Objects will float in liquids that are denser than it and will slowly sink in liquids that are
less dense. They won’t sink or rise in liquids that are of the same density. In a lava
lamp, as stated above, they will float up and down due to their change in density. In a
few hours, the blobs inside of a lava lamp will be in a state where they are denser than
the liquid and less dense. That is why the blobs rise and fall so often. This is kind of like
when a helium balloon rises up into the air. That’s because it is less dense than the air,
causing it to rise. When the balloon is deflated, it falls back to the ground because it
became denser than the air. This is mainly how density works.
As specified before, the process of having a lava lamp with actively moving blobs is very
slow. That’s because it takes a while for the lava lamp to completed heat up. On
average, it takes about 45 minutes for a lava lamp to be in a state where it can
successfully create floating and sinking blobs. Though in a cold room, it could take 2-3
hours.
Commonly, the light bulbs used in lava lamps are 25-40 watts. Light is made of tiny
particles. Light is a form of energy and it can also get energy-and momentum-from the
particles. The particles are basic units of light. They are also called light photons. Light
is what heats up the blobs in the lava lamp to push them up. The light photons are what
energize and create this light.
MATERIALS & METHOD
• 2 identical lava lamps
• 1 timer
• 1 temperature scanner
• 1 towel
Here is the method used during the experiment. The first lava lamp is turned on. The
temperature is measured with the temperature scanner; against the outside of the lava
lamp, after it has completely heated up for four hours. Next the second lava lamp was
turned on. The temperature was measured, again with the temperature scanner outside
of the lava lamp, also after it has completely heated up for four hours. Lastly the results
were compared. The dependent variable of this experiment is the amount of degrees
that the lava lamp increases every minute. The independent variable is the part of the
experiment that is being changed. The independent variable of this experiment is how
long the lava lamp has been turned on, while being measured. The control is when the
lava lamp is turned off. It is at the rate of 0 degrees Celsius per minute. There are many
controlled variables in this experiment; such as the exact amount of time that the lava
lamp is being turned on before being measured, the environment that the lava lamp is
in, the timer, and the person who is timing. This is a controlled experiment, because
there is only one variable. That variable is the amount of time that the lava lamp is
turned on before the temperature is measured.
Lava lamps actually are very hazardous, in certain situations. A death was caused by a
lava lamp in 2004; when a man heated a lava lamp on a stove. Of course, the heat
caused the lava lamp to explode. There were many causes to the death; the sharp
pieces of glass, the hot liquid from the lamp and they created a fire hazard that was very
dangerous. The main reason that this happened is that the heat burst the lamp open
with pressure. The lesson learned is to be very careful with extremely heating any glass
container. When experimenting with heat and a lava lamp, be sure to get a distance
away from it and wear safety goggles.
For the second experiment, a 10 liter bottle must be filled 3/4 with vegetable oil and 1/4
with water. Next, 5-10 drops of red food coloring were mixed with the vegetable oil and
water until it created a bright red liquid. Small pieces of Alka-Seltzer were also put into
lamp, to create bubbling results. Now this experiment needs to be tested with the liquid
cold, warm and room temperature to see the difference in how long the bubbles work. A
timer will be used to time this. The purpose of this experiment is to see if different
temperatures cause the lava lamp to work better or worse. The dependent variable is
how many minutes the lava lamp works for without stopping. The independent variable
is the temperature that each lava lamp is put to. The control of this experiment is the
room temperature lava lamp, since that was the one that worked in the first place.
For the third experiment, the heat of the cylinder shaped lava lamp will be compared to
the cone shaped lava lamp to see if the shape affects the rate of heating. The
temperature of each one will be measured with a temperature scanner while they are
turned off and also when they have been completely heated up-after four hours. The
control of this experiment is the cone shaped lava lamp. The dependent variable is the
heat difference of each lava lamp, measured in degrees Celsius. The independent
variable of this experiment is the shape of the lava lamp; varying for cone to cylinder.
The purpose of the fourth experiment is the find out whether or not different types of
candy will make the lava lamp work; replacing the Alta Seltzer. The control is the lava
lamp being used with the Alta Seltzer. The dependent variable is how long the bubbles
last, if they even form. The independent variable of this experiment is the different type
of candy being dropped into the bottle lava lamp. It was hypothesized that the mentos,
life savers and Alta Seltzers would work. This is because after feeling them, they had a
similar texture and they are about the same side. When they are cut in half they have
the same flaky white inside. Since they are so similar the hypothesis was formed. The
method of this experiment is this: first, a skittle was dropped into the lava lamp. The
moment it hit the water the timer began and it timed how long bubbles floated up to the
top of the bottle, if any. Then this was tested with the other types of candy to find an
outcome.
RESULTS & DISCUSSION
The cylinder shaped lava lamp’s temperature was measured while it was turned off. The
cone was also. The cylinder had less with 21.7 degrees Celsius and the cone with 22.1
degrees Celsius. This was a very small difference, though it could affect the results of
the next part. Both lamps were measured once they were completely turned on and the
blobs were moving around. The cylinder shaped lamp did worse than the cone again.
The cone was at about 70 degrees and the cylinder was about 50 degrees. This
increase of cone may be because of this. The cone shaped lava lamp is used almost
every single day, whereas the cylinder shaped lava lamp is hardly used and has been in
a dusty closet for multiple months. The shape of the lamp may affect the rate of heating
thought it could also be the amount of usage.
Degrees When Turned Off (Celcius)
22.2
22.1
22
21.9
21.8
21.7
21.6
21.5
cylinder
cone
Shape of Lava Lamp
Figure 1: cone and cylinder lava lamps while off
Degrees When Turned On (Celsius)
80
70
60
50
40
30
20
10
0
cylinder
cone
Shape of Lava Lamp
Figure 2: cone and cylinder lava lamps while on
The heating rate of a regular, generic lava lamp was tested. In 0 minutes the lava lamp
started at about 20 degrees Celsius. Though it increases to about 60 degrees after 100
minutes. Lastly, the lava lamp increased to almost 70 degrees Celsius after 245 minutes
of running. When the lava lamp was turned off the blobs inside were not moving at all.
By 100 minutes the blobs were slowly floating around, but after 245 minutes they were
completely melted down and operating smoothly. This means it takes just about 4 hours
to fully heat up a lava lamp so that operates and functions well.
Type of Candy Being Dropped Into
Did it work? (yes or no)
Bottle
dots
no
skittles
no
sweet tarts
no
mentos
yes
tic tacs
yes
life savers
no
peppermints
no
alta seltzer
yes
In this experiment, different types of candy were dropped into the homemade lava
lamps to see if the lamp functioned as it did before with the alta seltzer. It only worked
with three of the eight different candies. It worked with the mentos, tic tacs and alta
seltzers. The others merely floated to the bottom of the lamp and caused no action
except for the little splash it created after being dropped inside. It was very interesting
when the mentos were dropped in. A large bubble came from the mentos and shot up to
How Long Bubbles Last (minutes)
the top of the lamp. This way relate to how mentos create geysers in soda bottles.
2.5
2
1.5
1
0.5
0
hot
cold
room temperature
Temperature of Homemade Lava Lamp
Figure 3: homemade lava lamps temperature
The first lava lamp was heated in an incubator and its temperature increased to 40
degrees Celsius. When the Alta Seltzer was dropped into the bottle, a large funnel
exploded from the bottom of the lamp, and bubbles spewed out of the lamp very quickly.
When the room temperature homemade lava lamp was tested, the bubbles popped out
from the bottom of the lamp at a moderate pace. It also created a very vague and thin
funnel shape. Last, the bottle that was cooled in a refrigerator was very slow and hardly
let out any bubbles and did not create a funnel at all. The heat creates more action and
tension inside of the lava lamp and the bubbles and funnel move a lot faster and
effectively. This means that the hypothesis that was made was correct; that the heated
lamp will last longer.
Type of liquid
Does it work with Alta Seltzer? (yes or no)
Water
yes
Sprite
yes
Pepsi
yes
Fanta
yes
Table 1: homemade lava lamps with Alta Seltzer
Type of Liquid
Does it work with glucose tablets? (yes or no)
Water
no
Sprite
no
Pepsi
no
Fanta
yes
Table 2: homemade lava lamps with glucose tablets
Type of Liquid
Does it work with mentos? (yes or no)
Water
yes
Sprite
yes
Pepsi
yes
Fanta
yes
Table 3: homemade lava lamps with mentos
Temperature of Lava Lamp (Celsius)
80
70
60
50
40
30
20
10
0
0 minutes
245 minutes
100 minutes
Amount of Time Turned On
Figure 4: the heating rate of a lava lamp
At 0 minutes, the lava lamp was at 22.1 degrees Celsius. After 100 minutes it heated up
to 60, and by 245 minutes it heated to about 67 degrees Celsius. The rate of heating in
about 1 minute is about half of a degree Celsius.
CONCLUSIONS
The hypothesis of the first experiment was not confirmed. This is because it was
hypothesized that in one minute the lava lamp’s heat would increase about 1 degree
Celsius. After testing, it turns out that it actually increases less than half of a degree
Celsius per minute. It is thought that this is the average speed that a lava lamp should
heat up, since this exact brand and style of lava lamp is sold in toy stores a lot. A way
that this experiment could be improved is if the temperature probe was placed actually
inside of the lava lamp rather than just on the outside interior. Another experiment that
could be conducted from this point could be the lava lamp to discover if there are more
precise and different results in exchange.
The hypothesis of the second experiment was also not confirmed, because it was
hypothesized that the cylinder shaped lava lamp would have a higher temperature than
the cone shaped lava lamp. Though it was proved that the cone shaped lava lamp was
at a higher temperature while it was turned off and while it was turned on. This is
probably because since the cone shaped lava lamp is a triangular shape, the light will
be aimed in a different direction then the cylinder lamp; which is almost shaped like a
sphere. A way that this could improve is watching the process while the lava lamps are
heating up to observe the difference in the way that the blobs move around. An
experiment that could be performed after this is a comparison of lava lamps that are
different colors rather than shape.
The hypothesis of the third experiment was proved correct. This is because the
homemade lava lamp that had been heated to 155 degrees Celsius was the one that
worked for the longest amount of time. It is thought that this happened because all of
the heat built up inside of the water and just exploded in reaction of the alta seltzer
being dropped into it.
The hypothesis of the fourth experiment was not completely confirmed. It was
hypothesized that the homemade lava lamp would work when mentos, alta seltzer, life
savers and tic tacs were dropped into it. Some was correct and incorrect, because the
Alta seltzer, mentos and tic tacs worked. The dots, dots, skittles, sweet tarts,
peppermints and life savers did not work. This experiment could be improved by using
lots of other types of candy as well as the others.
The hypothesis of the fifth experiment was proved incorrect, because it was
hypothesized that the Fanta soda would work best replacing the water in the homemade
lava lamps. The coke worked the best. This is probably because coke works the best
creating a geyser with mentos, and mentos were also used in this experiment. They
create a reaction that causes a spout; even in different situations.
REFERENCES
Harris, Tom. "How Lava lamps Work." http://home.howstuffworks.com/lava-lamp.htm.
HowStuffWorks.com. 13 October 2000. Web. 24 January 2013.
Graham, Ian. “Science rocks.” DK Publishing, 2001. Print.
“Lava lamp.” http://en.wikipedia.org/wiki/Lava_lamp. Wikipedia, the free encyclopedia.
January 22, 2013. Web. January 24, 2012.
"Walker, Edward Craven." Britannica Book of the Year, 2001. Encyclopædia Britannica
Online School Edition. Encyclopædia Britannica, Inc., 2013. Web. 22 Jan. 2013.
http://school.eb.com/eb/article-9345026.
Wiley, John. "Nature of Matter." National Geographic Society, 2002. Print.