Term and Concepts for Background Research
- Surface tension is a property of the surface of a liquid that allows it to resist an external force.
- Viscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or tensile stress.
- Dipole-dipole forces are attractive forces between the positive end of one polar molecule and the negative end of another polar molecule.
- An ion-dipole force is an attractive force that results from the electrostatic attraction between an ion and a neutral molecule that has a dipole.
- Colloid is a system in which finely divided particles, which are approximately 10 to 10,000 angstroms in size, are dispersed within a continuous medium in a manner that prevents them from being filtered easily or settled rapidly.
- Saturated fat is fat that consists of triglycerides containing only saturated fatty acids; therefore, saturated fat is polar molecule.
- Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form in a biologically functional way. Proteins will denaturize at high temperature.
- Hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, such as N, F or O.
Hypothesis
My hypothesis, for my science fair project, is that as temperature increases, viscosity and surface tension both decrease. Since viscosity and surface tension are both properties of liquid, there is a relationship between them that surface tension varies directly as viscosity with temperature being constant.
Methods of Procedure
Viscosity
- Boil water in the electrical kettle. Measure 0.2L of water in the measuring cup eight times. Put 0.2L of water into 8 identical glass cups.
- Put six of the glass cups into the refrigerator in order to cool them down. Each cup of water will remain in the refrigerator for different periods of time. The reason for this is that each cup needs a different core temperature.
- Put one cup on the counter, and use the other one to do Step 4 so as to have different high temperatures.
- Pour the water through the funnel while measuring time using a stop watch for all 0.2L water to pass through the funnel.
- Repeat Step 4 with the six glass cups in the refrigerator and one cup on the counter to get flowing times at different temperatures.
- Repeat Step 1-Step 5 on different liquids: Coke®, milk, and vinegar.
Surface Tension
- Put several identical glass cups on the table; chill water in a large container in the freezer, and boil water on the stove.
- Combine the chilled water and boiling water in each cup to achieve different compositions of chilled water and boiling water and stir the water in order to get different temperatures.
- Put a small piece of identical paper on the surface of the water of each cup for better pressure distribution.
- Put paper clips on the paper in each cup until the paper clips begin to fall; measure the temperature of each cup when the paper clips start to fall down.
- Repeat the same procedures for vinegar, Coke® and milk.
Results
1. Water
|
Temperature (℃) |
Mass of Paper Clips staying on 0.2L water above the paper(g) |
Temperature (℃) |
Mass of Paper Clips staying on 0.2L water above the paper(g) |
|
7.41
|
9.81
|
52.9
|
3.06
|
|
12.1
|
8.50
|
57.2
|
2.72
|
|
14.7
|
7.82
|
66.0
|
2.04
|
|
16.9
|
7.14
|
74.2
|
1.70
|
|
26.2
|
5.10
|
82.3
|
1.70
|
|
27.4
|
5.10
|
85.1
|
1.36
|
|
34.2
|
3.40
|
87.7
|
1.36
|
|
51.1
|
2.38
|
92.5
|
1.02
|
|
Temperature(℃)
|
Time of flowing 0.2L water through the funnel
|
Temperature(℃)
|
Time of flowing 0.2L water through the funnel
|
|
2.5
|
9.9 sec
|
45.5
|
7.4 sec
|
|
13
|
8.9 sec
|
57
|
7.2 sec
|
|
15.5
|
8.4 sec
|
80
|
6.7 sec
|
|
36.5
|
7.9 sec
|
91
|
6.2 sec
|
|
40
|
7.5 sec
|
97
|
5.9 sec
|
Using the equation of water surface tension from Page 6 to substitute in the equation of water viscosity, we arrive at this equation:
Viscosity=0.2995(Surface Tension-16.966) +11.251
2. Coke®
Coke® Surface Tension
|
Temperature (℃) |
Mass of Paper Clips staying on 0.2L coke above the paper(g) |
Temperature (℃) |
Mass of Paper Clips staying on 0.2L coke above the paper(g) |
|
1.92
|
11.9
|
40.4
|
4.08
|
|
4.82
|
9.86
|
53.8
|
4.08
|
|
10.7
|
9.18
|
67.2
|
2.72
|
|
23.8
|
5.44
|
87.4
|
2.04
|
|
37.7
|
3.74
|
90.5
|
1.36
|
|
Temperature(℃)
|
Time of flowing 0.2L coke through the funnel
|
Temperature(℃)
|
Time of flowing 0.2L coke through the funnel
|
|
2
|
9.5sec
|
50
|
7.9 sec
|
|
16
|
8.7 sec
|
52
|
7.7 sec
|
|
29
|
8.1 sec
|
70
|
7.5 sec
|
|
37
|
7.9 sec
|
102
|
7.1 sec
|
Using the equation of Coke® surface tension from Page 8 to substitute in the equation of Coke ® viscosity, we arrive at this equation:
3. Vinegar
Vinegar Surface Tension
|
Temperature (℃)
|
Mass of Paper Clips staying on 0.2L vinegar above the paper(g)
|
Temperature (℃)
|
Mass of Paper Clips staying on 0.2L vinegar above the paper(g)
|
|
1.06
|
12.24
|
34.3
|
4.08
|
|
3.78
|
9.86
|
42.1
|
3.06
|
|
8.57
|
7.82
|
56.8
|
2.04
|
|
19.1
|
5.1
|
63.3
|
1.7
|
|
23.6
|
5.1
|
81.5
|
1.02
|
|
Temperature(℃)
|
Time of flowing 0.2L vinegar through the funnel
|
Temperature(℃)
|
Time of flowing 0.2L vinegar through the funnel
|
|
4
|
10.3sec
|
58
|
7.9sec
|
|
16
|
9.1sec
|
74
|
7.3sec
|
|
31
|
8.4sec
|
87
|
6.9sec
|
|
35
|
8.2sec
|
103
|
6.5sec
|
Using the equation of vinegar surface tension from Page 10 to substitute in the equation of vinegar viscosity, we arrive at this equation:
Viscosity=0.3551(Surface Tenson-13.031) +11.377
4. Milk
Milk Surface Tension
|
Temperature (℃) |
Mass of Paper Clips staying on 0.2L milk above the paper(g) |
Temperature (℃) |
Mass of Paper Clips staying on 0.2L milk above the paper(g) |
|
0.53
|
13.26
|
39.7
|
4.42
|
|
5.37
|
9.52
|
47.1
|
3.06
|
|
9.54
|
8.16
|
67.4
|
2.72
|
|
16.8
|
6.46
|
85.1
|
3.06
|
|
20.5
|
6.12
|
92.7
|
2.04
|
|
Temperature(℃)
|
Time of flowing 0.2L milk through the funnel
|
Temperature(℃)
|
Time of flowing 0.2L milk through the funnel
|
|
2
|
9.7sec
|
54.5
|
8.1sec
|
|
7
|
9.2sec
|
64
|
7.7sec
|
|
17
|
8.9sec
|
89
|
7.4sec
|
|
30
|
8.5sec
|
102
|
7.1sec
|
Using the equation of milk surface tension from Page 12 to substitute in the equation of milk viscosity, we arrive at this equation:
This graph summarizes all the previous relationships between Surface Tension and Temperature for all liquids.
This graph summarizes all the previous relationships between Viscosity and Temperature for all liquids.
*I simply left the unit of Surface tension as grams as it was measured in the experiments.
This graph summarizes all the previous relationship between Surface Tension and Viscosityfor all liquids.
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