Blog Activity 1: Scientific Method

1. Pictures

                             (cold water = regular water)

                       

                       

2.   Hypothesis

• Does hot water or cold water freeze faster? My hypothesis to this question is based on the difference of temperature leading me to believe that cold water would freeze faster than hot water because the temperature of the cold water is closer to freezing than the temperature of the hot water. 
• Does hot water or cold water boil faster? My hypothesis to this question is based on the difference of temperature leading me to believe that hot water would boil faster than cold water because the temperature of the hot water is closer to the boiling point than the temperature of the cold water.
• Does salt water freeze faster or slower than regular water? My hypothesis to this question is based on a real world application. Salt brings up the temperature of ice in the winter melting it on sidewalks. I believe that the regular water will freeze before the salt water because it disrupts the bonding between other water molecules. 

3. 

Boiling Experiment

Freezing Experiment

4.

 Boiling Experiment (Trial 2)

Freezing Experiment (Trial 2)

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Boiling Experiment (Trial 3)

 Freezing Experiment (Trial 3)

5. Controlled Variables:

 Boiling Experiment: 

• Same amount of water was used per trial (200 mL).
• Each time the water was boiled it was in the same size sauce pot.
• The pot was allowed to cool down completely by running it under water for ten minutes and letting it sit for 20 minutes after every use.
• The burner was turned on high to ensure the same amount of heat was used every time.
• Same timer was used per trial (phone timer).
• Starting water temperature was attempted to be controlled in every trial as best as possible. 

Freezing Experiment:

• Same amount of water was used per trial (50 mL).
• Same size and style cup was used for each variable water type.
• The placement within the freezer was identical for every trial.
• The same amount of salt was used for every trial of salt water. 
• Starting water temperature was attempted to be controlled in every trial as best as possible.

6.

The theory behind my hypotheses is based of the idea of phase changes. When a liquid's particles are cooled down under a specific pressure they can go through the phase change of freezing and become a solid. When a substance's temperature is closer to the temperature need to go through a phase change it will take less time to get to that point and go through with it than a substance with a temperature that is farther away. 

7. 

8.

http://www.youtube.com/watch?v=KCL8zqjXbME 

9.

• The scientific method begins by doing background research. For my experiment I did a little bit of dig on the outcome of each event by searching on the internet for reasons why the results occurred in similar experiments.
•  The next step in the scientific method was to identify a question or a problem. These questions were asked for us in the beginning of the experiment by asking what temperature water freezes faster, what temperature water boils faster, ect.
• Next comes formulating a hypothesis. This is answering the questions that were asked with the previous background research in mind.
• Following that comes the experimentation. We did this by controlling variables that were stated above to obtain the most accurate results possible. 
• Next we identify independent and dependent variables. For example, the salt in the water raises the temperature of the water which would be considered the independent variable and the dependent would be the water not freezing.
• After that we have to ensure that we continued on with the same setup. For example it might of been better to try and get the starting water temperature the same for every trial.
• Lastly, record the results and if not consistent with the hypothesis restart. Luckily, my results matched my hypotheses.

10.

The reproducibility of the experiment would be very easy to do because if someone were to come into the experiment not knowing anything they could look at my controlled variables. After reading the controlled variables and proceeding in the same exact fashion as I did they would be able to get similar results. The average values for the experiments are as follows:

Water Boiling

Hot Water Time: 152 sec

Cold Water Time: 263 sec

Water Freezing

Cold Water: 7073 sec

Hot Water Time: 7533 sec

Regular Water Time: 7173 sec

Salt Water Time: NA

11.

Matter is all around us and can be found in various forms. These forms are better known as states of matter and they include solid, liquid and gas. These states of matter interact on a daily basis and substances that are in one state can change into others. This is known as a phase change. Phase changes are dependent on temperature and pressure. At certain temperatures a liquid can be heated up to evaporate and become a gas. Likewise, a liquid can be cooled down to become a solid. In this lab we explored the states of matter and how temperature effects the ability of a substance to change from one state to another.

In this lab we preformed two different type of experiment and preformed them three times each. For the first experiment we observed which type of water boils faster, cold or hot. In this experiment we had to control many variables to make sure that the only thing that effected the results was the temperature of the water. The variables that were controlled are stated above. The results showed that hot water boiled faster than cold water which makes logical sense. When thinking about it logically we know that water at a temperature closer to the boiling point will reach it sooner than water is colder. The second experiment we explored weather or not temperature and salt effected freezing. Like the first experiment, controlled variables were defined to ensure that the only temperature or salt effected the results. The results came out to be very logical where the coldest water froze first and the salt water froze last.

In the boiling experimentation portion of the lab I found that hotter water boils faster than cold which is probably used everyday in kitchens around the world. If someone wants their pasta to be cooked faster they would probably start the cooking with hot water to make sure that food gets done faster. In the second experiment I observed weather or not salt water freezes faster than normal water and found that it did not. If we apply real world concepts to this idea we can understand why the results came out the way they did. For example, when ice covers the side walk we lay salt down to raise the temperature of the ice to and stop it from forming.

References:

"File:Water molecule.png - Wikimedia Commons." Wikimedia Commons. N.p., n.d. Web. 22 July 2013. <http://commons.wikimedia.org/wiki/File:Water_molecule.png>.

"States of Matter - YouTube." YouTube. N.p., n.d. Web. 22 July 2013. <http://www.youtube.com/watch?v=KCL8zqjXbME>.