Blog Post 1, Activity 1

Activity 1:
 

Experiment 1:

Question: Does hot water or cold water freeze faster?

Hypothesis: Cold water will freeze faster than hot water.

Materials used:

·         1 ice cube tray

·         1 Tbsp measuring spoon

·         Labels

·         Hot water

·         Cold water

Process:

1.       Fill 1 ice cube tray compartment with 1 Tbsp of cold water

 

2.       Repeat step 1 two times to end up with three ice cube compartments full of cold water (leave one compartment empty in between each filled compartment so the temperature of one ice cube compartment does not affect another)

 

3.       Label the row as cold water

4.       Fill 1 ice cube tray compartment with 1 Tbsp of hot water

5.       Repeat step 4 two times to end up with three ice cube compartments full of hot water (leave one compartment empty in between each filled compartment, so the temperature of one ice cube compartment does not affect another)

6.       Label the row as hot water

7.       Place ice cube tray in freezer

8.       Start stopwatch

9.       Record time for each trial when the water is frozen

Variables:

The independent variable is temperature of the water and the dependent variable is the time it takes for the water to freeze.

Controlled Variables:

·         Same ice cube tray

·         Same freezer (both hot and cold put in at the same time)

·         Same measuring utensil

·         Same water source (for both hot and cold)

Results:

	Trial 1	Trial 2	Trial 3
Cold Water	38 minutes	40 minutes	41 minutes
Hot Water	42 minutes	43 minutes	45 minutes

Theory/Conclusion:  Cold water freezes faster than hot water.

 

 

Experiment 2:

Question: Does hot water or cold water boil faster?

Hypothesis: Cold water will boil faster than hot water.

Materials used:

·         Cold water

·         Warm water

·         1 cup measuring cup

·         1 small pot

·         Stop watch

 

Process:

1.       Fill a 1 cup measuring cup up with cold water

2.       Dump the 1 cup of cold water into the small pot

3.       Turn on the burner

4.       Start the stopwatch

5.       Observe the water and wait for it to begin boiling

6.       Record the time the water began boiling

7.       Dump out the water from the pot

8.       Let the pot and burner cool to room temperature

9.       Repeat this process two more times

10.   Fill a 1 cup measuring cup with hot water

11.   Dump the 1 cup of hot water into the small pot

12.   Turn on the burner

13.   Start the stopwatch

14.   Observe the water and wait for it to begin boiling

15.   Record the time the water began boiling

16.   Dump out the water from the pot

17.   Let the pot and burner cool to room temperature

18.   Repeat this process two more times

Variables:

The independent variable is the temperature of the water and the dependent variable is the time it takes for the water to boil.

Controlled Variables:

·         Same pot

·         Same measuring utensil

·         Same stove

·         Same burner (set to the same heat each time)

·         Same water source (hot and cold)

Results:

	Trial 1	Trial 2	Trial 3
Cold Water	3 minutes 57 seconds	4 minutes 01 second	3 minutes 58 seconds
Hot Water	3 minutes 34 seconds	3 minutes 34 seconds	3 minutes 37 seconds

Theory/Conclusion: The hot water boiled faster than the cold water.

 

Experiment 3:

Question: Does salt water freeze faster or slower than regular water?

Hypothesis: Salt water will freeze slower than regular water.

Materials Used:

·         Water

·         Salt

·         1 glass

·         1 Tbsp measuring spoon

·         1 ice cube tray

·         Labels

·         Stopwatch

Process:

1.       Fill 1 ice cube tray compartment with 1 Tbsp of regular water

2.       Repeat step 1 two times to end up with three ice cube compartments full of regular water (leave one compartment empty in between each filled compartment, so the temperature of one ice cube compartment does not affect another)

3.       Label the row as regular water

4.       Fill a glass with water

5.       Add salt to the glass

6.       Thoroughly stir the salt and water until the salt has dissolved in the water

7.       Fill 1 ice cube tray compartment with 1 Tbsp of salt water

8.       Repeat step 7 two times to end up with three ice cube compartments full of salt water (leave one compartment empty in between each filled compartment, so the temperature of one ice cube compartment does not affect another)

9.       Label the row as salt water

10.   Place ice cube tray in freezer

11.   Start stopwatch

12.   Record time for each trial when the water is frozen

Variables:

The independent variable is the type of the water and the dependent variable is the time it takes for the water to freeze.

Controlled Variables:

·         Same ice cube tray

·         Same freezer (both regular and salt water put in at the same time)

·         Same measuring utensil

·         Same water source

·         All of the salt water was mixed in the same glass so the salt equally dissolved and distributed

Results:

	Trial 1	Trial 2	Trial 3
Regular Water	56 minutes	53 minutes	58 minutes
Salt Water	70 minutes	74 minutes	66 minutes

Theory/Conclusion: Salt water freezes slower than regular water.

Extra Questions:

Numbers 1, 2, 3, 4, 5, & 6 are answered in the experiment write-up.

7. Include an image of the atoms that make up water molecules.

"Chemistry Review: Physical Change in Solids." ACS Chemistry for Life. American Chemical Society, 2013. Web. 10 July 2013.

 

8. Include/embed a video or animation that shows how water molecules are arranged in the three states of matter for water.

                http://www.youtube.com/watch?v=v12xG80KcZw

9. Describe the scientific method/process and how each step correlates to your own experiments.

 

The scientific method is a step-by-step method that is used when conducting experiments. The first part of the scientific method is to find out the question you are going to answer. For my experiments the questions I was going to answer were does hot water or cold water freeze faster, does hot water or cold water boil faster, and does salt water freeze faster or slower than regular water. The second step is to do background research. For each of these experiments I looked for the best way to complete the experiment so that I would get the least amount of variables possible and refrain from any biases. The third step of the scientific method is to come up with your hypothesis. The point of a hypothesis for you to make an educated guess as to what your outcome will be. In these experiments my hypothesizes were cold water will freeze faster than hot water, cold water will boil faster than hot water, and salt water will freeze slower than regular water. The fourth step is to test your hypothesis by completing your experiment. By completing your experiment you will be able to see whether or not your hypothesis was correct. In order for the experiment to be accurate you must have controlled variables and you must be able to complete the experiment multiple times without having a varying conclusion. In the three experiments I completed I had to time how long it took to freeze hot and cold water, time how long it took to boil hot and cold water, and time how long it took to freeze salt and regular water. The fifth step is to record your results. This is important because people are able to see how you came up with the results that you did. Usually these results are shown in the form of a graph or chart, just as mine are in each of my three experiments. The sixth, and final, step of the scientific method is to draw your conclusion and report it. Your conclusion will be able to tell you whether or not you made a correct hypothesis. It is important to report your conclusion so that people are able to see the experiment you conducted, and how you came up with the conclusion you did. In my experiments my conclusions were that cold water freezes faster than hot water, hot water boils faster than cold water, and regular water freezes faster than salt water.

10. Talk about the reproducibility of the experiment? What are the average values?

 

Each of these experiments can easily be repeated. When I repeated the experiments my values were all very similar. In the first experiment my average value for cold water was 39.667 minutes and for hot water was 43.333 minutes. In the second experiment my average value for cold water was 3 minutes and 59 seconds and for hot water was 3 minutes 35 seconds. In the third and final experiment my average value for regular water was 55.667 minutes and for salt water was 70 minutes.

 

11. Write a three paragraph statement about your experiment and connections to a real‐world application. First paragraph: intro of the science concepts. Second paragraph describe your experiment, data and conclusions. Third paragraph: apply your science concepts and knowledge to a real-world application. After reading these paragraphs, a person should realize why these science concepts are important while gaining knowledge related to the topic.

 

In these three experiments, that I conducted, I was able to learn and better understand a few science-related concepts. I learned a lot about states of matter. This includes how water can change from a gas, to a liquid, to a solid, and vice versa. I also discovered more about the boiling point and freezing point of water. Finally I gained knowledge on how the temperature of water affects what you are trying to do with it, in this instance boil and freeze it.

Each of the three experiments I conducted were completed in my house. I used ice cube trays, pots, measuring utensils, and water from my house. I made sure to equally measure out the hot and cold water and the regular and salt water in order to refrain from biases. I also made sure to use the same ice cube trays and pot when I completed the experiments. By keeping these variables consistent I was able to keep my experiments bias-free. To collect my data I completed each of these experiments three times and then I found the averages of the three trials. This way I knew that my results would be accurate. I concluded that cold water freezes faster than hot water, hot water boils faster than cold water, and regular water freezes faster than salt water.  

I think that all three of these experiments were very helpful and applicable to the real-world. I boil water and freeze water on a daily basis and I have never thought to test whether hot water or cold water is faster in these two situations. After completing these experiments I now know that I should use hot water in my pot when I am going to boil water, and that I should use cold, regular, water in my ice cube trays when I am going to freeze water. Also, after completing these experiments I know about how long it takes to complete these tasks. This is helpful because now I will be able to better plan for how long I need to set aside when I am boiling and freezing water.