1. ALEX DAUGHTRY's Lab Result
Name: ALEX DAUGHTRY
Partners: ASHWIN BHAKRE
Date of experiment: Thursday, September 30, 2010
Which of the following starting temperature of water (60, 70 and 80 degree
Celsius) will cool down the most in 10 minutes?
Aim: We are trying to find out if water takes longer time to coo down if the starting
temperature are different?
Hypothesis: We think the hotter water the water is, the longer it takes to cool down.
Variables:
Input variable: The room temperature could be different when we are doing the
measuring water in two different periods, the container could be the different size that
would cause the water in bigger container will cool down faster.
Output variable: the starting temperature ( 70 degree Celsius, 60 degree Celsius
and 80 degree Celsius
Control variables:
Control variable 1: Container. I can use the same container that has
same shape, same material and the same
Control variable 2: Room temperature. We can't finish three measuring in
one period, so there's nothing we can do about the room
temperature.
Control variable 3: we give them the same time to cool down: 10 minutes
Materials:
Test tube, Tripod, Bunsen Burner, thermometer for boiled water, dropper,
measuring pot 150 ml, beaker 250 ml, timer, clamp, gauze mat

2. ALEX DAUGHTRY's Lab Result
Method:
The starting temperature of 60 degree Celsius's water was the coolest in ten
minutes.
Results:
100
75
50
25
0
1 2 3 4 5 6 7 8 9 10
STARTING TEMP - 60˚C
STARTING TEMP - 70˚C
STARTING TEMP- 80˚C
Conclusion:
• the x row is the time that the water cool down, it showed what's the
temperature of the water of each minute , y row is the temperature of the water
• Cooler water gets closer to the freezing point because the proton is moving
slow but the proton in the hot water is moving so fast so it takes longer to slow
down.

3. ALEX DAUGHTRY's Lab Result
• The Impurity of the water is hard to measure because sometimes it could the
Mpemba effect may cause the data not reliable.
Evaluation:
• Our method gave us a reliable data, because We controlled every single
variable changes that we can control, we count time using seconds, we are
concentrate on doing the experiment. comment on the reliability of your
method.
• If we have more time and more people doing this project, we might finish two
or all the experiment in one period, then the room temperature might not be
that effective to our results.
• I can do the research about the effect of the Impurity of the water to cause the
time to cool down the water. Because the Mpemba effect (The effect is named
for the Tanzanian high-school student Mpemba. Mpemba first encountered the
phenomenon in 1963 in Form 3 of Magamba Secondary School, Tanzania
when freezing hot ice cream mix in cookery classes and noticing that they
froze before cold mixes. After passing his O-level examinations, he became a
student at Mkwawa Secondary (formerly High) School, Iringa, Tanzania. The
headmaster invited Dr. Denis G. Osborne from the University College in Dar
Es Salaam to give a lecture on physics. After the lecture, Erasto Mpemba
asked him the question "If you take two similar containers with equal volumes
of water, one at 35 °C (95 °F) and the other at 100 °C (212 °F), and put them
into a freezer, the one that started at 100 °C (212 °F) freezes first. Why?" only
to be ridiculed by his classmates and teacher. After initial consternation, Dr.
Osborne experimented on the issue back at his workplace and confirmed
Erasto's finding. They published the results together in 1969.) is still yet
unsolved. I wanna challenge myself. But it could take a long time.
Man I have nothing to say about my work. I spend 8 hours to work at it, but
teachers only count the lowest grade, so I only have 1-1-4 of my hard
work. Although this is unfair but I have to think carefully. Now, how come
there are someone still get a high grade? They are been graded in this
unreasonable standard, too. What I realized is that I am not a bad student,
I found that all the questions that I understand have been answered very
well, except for the questions that I don't even understand, think about it, if
you had a successful experiment, but you don't understand what info
should be collected then you are doing nothing. I need to discuss this
problem with Ms. Barnes to see what shall I improve.