### Present Remotely

Send the link below via email or IM

• Invited audience members will follow you as you navigate and present
• People invited to a presentation do not need a Prezi account
• This link expires 10 minutes after you close the presentation

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

# VARIATIONS IN WATER TENSION

No description
by

## Maria Paula Hernandez Gutierrez

on 15 March 2016

Report abuse

#### Transcript of VARIATIONS IN WATER TENSION

By: Maria Paula H, Santiago Serna, Nicolas Zamudio.
Scientific Question
Pictures and videos
Safety Concerns
Independent variable:

Variables
if water has salt and gets hotter then surface tension of the water will increase.

And Procedure
Materials
1. First label the 2 beakers "salt water" and "pure water".
2. Fill each beaker with 200ml of distilled water.
3. In the beaker labeled "salt water" add 2 table spoons of salt.
4. Then place the 2 beakers in the refrigerator until both reach 15C.
5. Confirm the beaker temperature using a thermometer.
6. Place the 1x1cm piece of aluminum foil floating in both beaker.
7. Start placing rice grains on the aluminum foil until it sinks.
8. Record the number of rice grains placed on each aluminum foil.
9. Take the 2 beakers to a room temperature of 25C and repeat the process.
10. Place the two beakers on a hot plate and heat them up to 35C and repeat the process.
11. Record results and draw conclusions.

Why did we choose this project?
We chose this project because we are really interested to see how to manipulate this strange natural phenomenon, because this may help develop new technologies.
How does salt and different temperatures affect the surface tension of water?
Background research
water tension:
water tension is the property the water surface has to resist external forces, this phenomenon happens when the water surface meets with a gas, making a thin layer created by cohesive forces.
Hypothesis
Water temperature and salt.
Dependent variable:
Surface tension of water. (number of rice grains before aluminum sinks)
Constants:
Amount of water, size of the aluminum foil, rice grain size.
Control:
Room temperature water without salt.
Materials
1. 2 beakers
2. 400ml distilled water
3. A measurement cylinder
4. 2 tablespoons of salt
5. a cup of rice grains
6. two pieces of 1x1cm of aluminum foil
7. refrigerator
8. hot plate
Procedure
History of our topic:

Many researchers throughout history have studied this natural phenomenon and searched for its cause and possible uses of it. some of this researchers were Agnes Pockels, who studied how to use this effect in dish washing, and Benjamin Franklin.
The only safety concern in our experiment is that we are working with hot water, so you have to be careful not to burn yourself or others.
They have recently discovered a particle capable of manipulating water tension at will, giving foot to new inventions.
Trial 1
Trial 2
Trial 3
Average
Water conditions
room temp.
w/o salt
cold temp.
with salt
room temp.
with salt
cold temp.
w/o salt
hot temp.
w/o salt
hot temp.
with salt
# of rice grains in tinfoil before sinking
83
132
51
28
74
43
91
134
67
36
63
47
126
87
56
32
71
56
130.6
87
59
32
69.3
48.6
Materials
Of the Procedure

Photos

10
20
30
40
50
60
70
80
90
100
110
120
130
140
room temp w/o salt
room temp w/ salt
cold w/o salt
cold w/ salt
hot w/o salt
hot w/ salt
# of rice grains
Water conditions
Qualitative
Observations
Observations : As we saw in our experiments, there were some stunning "water bending" this was a sure an spectacular act, is good to take a moment to observe this natural phenomenon.
We saw before the tin foil sank how the water started to flood it.
We also were very impressed about about how much weight this strange phenomenon was able to support.
Conclusions
For Listening
Relation of water conditions and weight held
Effect of Temperature and Salt on Surface Tension
Introduction
Have you ever seen those cool little bugs that are able to walk on the water surface? well, this insects are able to do this prodigious act through the magic of surface tension! In our experiment, we will test the capacities of this phenomenon and test the amount of weight it is capable to hold before letting the object sitting in its surface sink.
Results
Result Summary
#1: Room temperature water without salt = 130.6 rice grains
#2: Room temperature water with salt = 87 rice grains
#3: Hot water without salt = 69.3 rice grains
#4: Cold water without salt = 59 rice grains
#5: Hot water with salt = 48.6 rice grains
#6: Cold water with salt = 32 rice grains

Here is the list in order of each type of water.
*In conclusion, our hypothesis was not supported since we predicted that hot water with salt would be the one to hold the most weight, but that place was taken by water at room temperature without salt.
*According to our research, this is because salt and high temperatures separate the molecules that create the surface tension.
Restate Hypothesis
Problems
Some problems we faced in our experiment were:

* The beakers we used were of different sizes, meaning one used more water than the other
* The pieces of tinfoil we used were very small, and sometimes rice bounced of them.
Areas of Improvement
A way we could improve our experiment for the next time is using beakers of the same size and cutting aluminum pieces of 3cm x 3cm.
Contributions to science
Our results contribute to science because with them many new technologies may be developed such as new water insulation techniques, water purifying systems, or even helping water vehicles be more efficient, which may not be great improvements, but do help the world in some ways.
Areas of Further Study
Some areas of further study may be the investigation of how to use this phenomenon on a much larger scale and for it to have more uses in our daily lives.
Full transcript