September 29, 2014.
Biology
Properties Of Water Adhesion
How does temperature change affect surface tension?
As the temperature of a liquid increases, its surface tension decreases. When water heats up, the movement of its molecules disrupts the imbalanced forces on the surface of the water and weakens its sheet-like barrier of tightly bound molecules, thereby lowering the surface tension. This is why hot water is more effective when cleaning; its low surface tension allows it to more easily penetrate the fibers of a material like fabric and wash away stains. ( www.classroom.synonym.com)
If I put one cup of water in two different places that are 70 degrees Fahrenheit, and 28 degrees Fahrenheit for twelve minutes, and then switch them, the water’s surface tension will change. I expect the paper to sink after I switch their locations. I am predicting that the paper will sink to the bottom and not float.
My independent variable is one cup of water and my dependent variables are my 70 degree and 28 degrees places.
First, I poured one cup of water into two different cups. The next thing I did was put one of the cups in a place that is 70 degrees Fahrenheit, and the other in a place that is 28 degrees Fahrenheit. I started a timer for twelve minutes after I finished step two. I stuck a piece of paper in both and recorded what happened.Then I switched the location of the two cups. The 70 degrees cup was moved to the 28 degrees place and the 28 degrees cup was moved to the place that is 70 degrees for another twelve minutes.
Independent Variable
Dependent Variable
Dependent Variable
Temperature
70 Degrees
28 Degrees
Observations at twelve minutes
The paper floated at the top of the water.
The water looked gooey
The paper stayed at the top of the water.
The water was cold.
Observations at twenty-four minutes The paper still floated on top of the water
The temperature was changed but