Cinthya Montoya
September 18, 2014
Period 4
Biology
Surface Tension of Water
I. Objective:
How does soap affect the surface tension of water?
II. Background:
The surface tension of water is due to cohesion forces that allow water to stick to its same molecules. In a liquid, such as water, molecules are strongly attracted by each other causing a phenomenon called surface tension of water. Surface tension could be defined as the force that implies a liquid to resist external forces produced by cohesive forces of the molecules in water.
III. Hypothesis:
If we put soapy water on the penny, then the penny will not hold the same amount of drops of soapy water as the penny with tap water because the soapy water is will not stick to itself.
IV. A. …show more content…
Procedure
1. We took the two pennies and with a napkin, we made sure they were clean and dry.
2. Then, we took the two beakers (one filled with soapy water and the second one with tap water) and designated one beaker for the two of us.
3. We introduced each pipet into a separate beaker, (One inside the soapy water and the other one inside the beaker with tap water) then we grabbed the liquids from the beakers and we started putting the drops of water in each coin.
4. As we slowly put the liquids above the coins, we counted how many drops of water each one could fit.
5. We continued the same procedures several, 4 more times and we recorded them in our data table.
V. Data:
Control: Tap water. Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Average
Tap water 29 25 26 17 24 24.2 Average: 29 + 25 + 26 + 17 + 24 = 121/5 = 24.2 Manipulated: Soap added to water. Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Average
Soapy water 16 20 10 12 18 15.2
Average: 16 + 20 + 10 + 12 + 18 = 76 / 5 = …show more content…
Our data proves that our hypothesis was correct because the penny with soapy water did not hold the same amount of drops as the first penny with tap water. In the data above, our penny with only tap water was able to hold more drops than the penny with soapy water. The average number of drops of tap water was 24.2, while the penny with soapy water was 15.2. This is possible because the soap that we added in the water breaks and decreases the molecules that are attracted and forming cohesion. There are two forces acting upon the coin’s surface. One of them is known as surface tension of water and the second one as cohesion. Cohesion refers to the molecules that are attracted to their same type. Surface tension of water is a special name used to name the cohesion formed between water
September 18, 2014
Period 4
Biology
Surface Tension of Water
I. Objective:
How does soap affect the surface tension of water?
II. Background:
The surface tension of water is due to cohesion forces that allow water to stick to its same molecules. In a liquid, such as water, molecules are strongly attracted by each other causing a phenomenon called surface tension of water. Surface tension could be defined as the force that implies a liquid to resist external forces produced by cohesive forces of the molecules in water.
III. Hypothesis:
If we put soapy water on the penny, then the penny will not hold the same amount of drops of soapy water as the penny with tap water because the soapy water is will not stick to itself.
IV. A. …show more content…
Procedure
1. We took the two pennies and with a napkin, we made sure they were clean and dry.
2. Then, we took the two beakers (one filled with soapy water and the second one with tap water) and designated one beaker for the two of us.
3. We introduced each pipet into a separate beaker, (One inside the soapy water and the other one inside the beaker with tap water) then we grabbed the liquids from the beakers and we started putting the drops of water in each coin.
4. As we slowly put the liquids above the coins, we counted how many drops of water each one could fit.
5. We continued the same procedures several, 4 more times and we recorded them in our data table.
V. Data:
Control: Tap water. Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Average
Tap water 29 25 26 17 24 24.2 Average: 29 + 25 + 26 + 17 + 24 = 121/5 = 24.2 Manipulated: Soap added to water. Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Average
Soapy water 16 20 10 12 18 15.2
Average: 16 + 20 + 10 + 12 + 18 = 76 / 5 = …show more content…
Our data proves that our hypothesis was correct because the penny with soapy water did not hold the same amount of drops as the first penny with tap water. In the data above, our penny with only tap water was able to hold more drops than the penny with soapy water. The average number of drops of tap water was 24.2, while the penny with soapy water was 15.2. This is possible because the soap that we added in the water breaks and decreases the molecules that are attracted and forming cohesion. There are two forces acting upon the coin’s surface. One of them is known as surface tension of water and the second one as cohesion. Cohesion refers to the molecules that are attracted to their same type. Surface tension of water is a special name used to name the cohesion formed between water