Question 1:
Does hot water or cold water freeze faster?
Hypothesis: I
believe that the cold water will freeze faster, due to the fact that the
molecules are at a slower rate of movement so they will be able to become solid
more quickly than the faster moving molecules of the hot water.
Materials:
1.
1 timer
2.
1 measuring cup
3.
Six small plastic cups
4.
Hot water
5.
Cold water
6.
Labels for cups
7.
Freezer at constant temperature
8.
Chart for making observations
Controlled Variables:
1.
Temperature of freezer, same freezer
2.
Size of cups
3.
Amount of water in cups
Data:
|
Water
|
Time Test 1
|
Time Test 2
|
Time Test 3
|
Average Time
|
|
Hot Water
|
64.33
|
66.4
|
62.41
|
64.38
|
|
Cold Water
|
54.23
|
54.45
|
53.58
|
54.09
|
Theory: I believe that because of the molecules
moving at a faster rate in the hot water, they had to slow down much more
before they could be condensed together into ice. This is why it took the hot
water so much longer to freeze than the cold water. In my experiment the
average times were almost a whole minute apart.
Question 2:
Does cold water or hot water boil fast?
Hypothesis: I
believe that hot water will boil faster because the molecules are already
moving faster so they will have more energy in them making them boil faster than
cold water.
Materials:
 |
 |
1.
Kitchen stovetop
2.
Kitchen pot
3.
Hot and cold water
4.
Timer
Controlled variables:
1.
Same stove
2.
Same pot
3.
Same amount of water
 |
| The setting on the stove was kept consistent at High for each test. |
Data:
|
Water
|
Time Test 1
|
Time Test 2
|
Time Test 3
|
Average Time
|
|
Hot Water
|
2.03
|
2.1
|
2.21
|
2.11
|
|
Cold Water
|
3.08
|
2.58
|
2.4
|
2.69
|
Theory: I believe
that due to the data recorded that Hot water does in fact boil faster than cold
water. Based off of these findings, I
believe it is because the molecules in hot water are already moving at a faster
rate. Molecules that are moving faster
have more energy, allowing them to become hotter faster and change from hot to
boiling.
Question 3:
Does salt water or regular water freeze faster?
Hypothesis: I
believe that the salt water will freeze slower because the salt keeps the water
molecules from attaching to each other at the same rate as if there was no
salt.
Materials:
1.
Salt
2.
Water
3.
Same size cups
4.
Measuring cups
5.
Freezer
6.
Timer
Controlled Variables:
1.
Amount of water
2.
Same Freezer
3.
Amount of Salt
Data:
|
Water
|
Time Test 1
|
Time Test 2
|
Time Test 3
|
Average Time
|
|
Salt Water
|
67.04
|
68.11
|
68.38
|
67.84
|
|
Plain Water
|
55.3
|
64.1
|
64.03
|
61.14
|
Conclusion: Salt water freezes slower than regular water.
Theory: I found
that the water with the salt solution froze much slower than the regular
water. I believe this occurred because
of the added substance in the water than slowed down the freezing process. The
water needed to overcome the solution of salt before it could freeze, which
took longer than the regular water did.
Images:
 |
| Water Molecule |
 |
| Saltwater molecules |
 |
| Salt Molecule |
Video of the
structure of water molecules in the three stages of matter.
Scientific Method:
1.
Ask A
Question: In this phase it is important that you ask a question so that you
have a specific set of data to be tested and looked at. In my experiments we were looking to see if
water boiled and froze at different rates related to their current temperature
and if they had a different mixture such as salt.
2.
Do
Background Research: It is very important to get background information for
your studies before you begin an experiment so that you have some knowledge of
what you are to be looking for and how the process will take place. For me, I looked up the images of the water
molecules again so that I could make accurate hypotheses before taking part in
the experiments on my own.
3.
Construct
a Hypothesis: This is very important for an experiment, because you need to
be looking for something specific and you won’t know if the experiment has
worked or failed if you haven’t made a hypothesis. The hypothesis tells what you might think
before you have done an experiment. I used what I already knew about water
molecules to decide which type of water would freeze or boil faster.
4.
Test
Your Hypothesis with experimentation: During the testing is when we take
measurements and write data to discover if our hypotheses are correct or
false. We document the results we find
and use that data to make charts, graphs, and tables to solve our questions.
Using the process of testing each question three times I was able to get a more
accurate set of data to fill in my chart.
I could use averages, which makes the experiment more accurate.
5.
Analyze
your data: This is a very important step because we look at our information
to decide if our hypotheses are correct.
In my case, I was correct in thinking that hot water would boil faster,
and that cold water would freeze faster, also that salt water would freeze
slower. We use what we learned in the
experiments to find our answer.
6.
Communicate
your results: When we do experiments we must show that we have found
answers to our questions so we have to state what we have found and why it has
happened that way. This makes for more
clear and accurate information about any certain experiment or question.
Repeatability of an experiment:
It is very important to repeat an
experiment in order to get an accurate result.
In this case, I repeated each of my experiments three times in order to
take an average of each testing. This
allowed me to have more data used creating a more accurate and truthful result
and conclusion. By taking more than one
measurement I am able to view more data and be able to write a better
conclusion to my findings. By doing it
more than once, I also lower my chances of error while documenting my data.
My experiment and its connections to real life
The scientific concepts
I looked at and worked with in these experiments are the states of matter in
relation to the molecule of water.
Through careful observation and testing, I worked with water in each of
its stages. Its solid state was tested
through discovering if hot or cold water froze faster, its liquid state was
also seen in this experiment as well as in the mixture of salt to determine if
the addition of salt would hinder or aid in the freezing process. Waters gas form was also witnessed in the
experiment with boiling points. I found
that water that is hot would make its state change more quickly into a gas, as
steam, faster than colder water.
In
my experiments I took three testing samples in each of the questions being
asked in order to gain a more accurate result.
I used careful measurements such as 1 cup of water for boiling, and ½
cup of water for freezing in order to keep consistent variables. In each of my experiments I also documented
the time it took for each change being tested to occur. In the boiling experiment I watched closely
with my timer to document the exact moment of a boil. I believed that the hot water would boil
faster than the cold, and with my data collected I concurred that my hypothesis
was indeed correct. For the freezing
test with hot and cold water I hypothesized that the cold would freeze faster,
and was also correct. This was because I
used my knowledge of molecules to note that the faster they are moving the
slower they would freeze. In the
experiment with salt I also hypothesized that the salt would freeze
slower. I decided this through outside
knowledge about ice on the ground in winter. We use salt to melt the ice
outside during the cold winter months.
To
use these experiments in real life I believe would be both helpful and
timely. If I were to be boiling pasta
for a team dinner I would know that by starting with hot water I could boil faster. Also, that if I needed ice cubes quickly I
would use cold water, because that would freeze much quicker than warm
water. And of course I already use salt
on my sidewalk, so I can continue that process knowing it is actually making the
sidewalk safer for myself and others walking on it.
No comments:
Post a Comment