Activity One

1. Does hot water or cold water freeze faster? 

 Hypothesis: I think that the hot water is going to freeze faster because the water will freeze throughout the container whereas cold water will create ice crystals on top causing it to freeze on top and slow down the freezing process for the rest of the water.

Materials: 
 1. Two - 18oz plastic cups
 2.  Measuring cup
 3. Thermometer
 4. Water
 5. Freezer
 6. Timer
 7. Labels

Setup:
 1. Fill the cups with 1 cup of hot or cold water and then are labeled accordingly.  
 2. Record temperatures of both the hot and cold water. 
 3. Place both containers into the freezer on level surface. 
 4. After 30 minutes, record the temperatures of both hot and cold water once again.  
 5. After 30 minutes, record temperatures again for both containers.
 6. Repeat process until water is completely frozen.  

Pictures:

1 - Taking temperatures before freezing

1 - Placing cups in freezer

 

1 - Taking temps at 90 minutes

1 - Cold (90mins) thicker ice on top

                                                                                                                                                                  

1 - Hot (90mins) ice formed on all sides

1 - Hot completely frozen at 180mins

2 - taking temperatures before

2 - Putting cups into freezer

2 - Taking temps at 120 minutes

2 - Hot water frozen completely

3 - Taking temps before freezing

3 - Taking Temps at 90 minutes

3 - At 90 minutes

3 - Hot water frozen before cold water

Data:




Controlled Variables: 
 1. Exact same cups for both hot and cold water (18oz plastic cups)
 2. Amount of water used for both hot and cold water (1 cup each)
 3. Same freezer used
 4. Same time intervals between temperature recordings (30 minutes)
 5. Same thermometer used to record temperatures

Formulated Theory:

Hot water freezes faster then cold water because the the hot water will start to form ice crystals throughout the container of water causing a more even freezing process, while the cold water will form ice crystals at the top of the container causing the freezing process to slow down.

Average values of repeated experiment:

After repeating the experiment three times, it allows me to average out the freezing time of both waters and allows a more realistic outcome. If i had only did the experiment once and based my findings off that experiment it might have shown completely different results. The average freeze time for the hot water was 180 minutes and the average freeze time for the cold water was around 210 minutes.

2. Does hot water or cold water boil faster?

 Hypothesis: I think that the hot water is going to boil faster for the simple fact that it starts off closer to the boiling point of water and therefore will have to heat up less then the cold water will have to.

Materials: 
 1. Two - 8 cup pans
 2. Measuring cup
 3. Thermometer
 4. Water
 5. Stove
 6. Timer
 7. Labels

Setup:

 1. Fill the pans with 6 cups or hot or cold water.

 2. Record temperatures of both the hot and cold water.

 3. Place both pans on stove top and turn heat onto "8" for both pans.

 4. After 2 minutes, record the temperatures of both hot and cold water

 5. After 2 minutes more minutes, record temperatures again for both pans

 6. Repeat process until water is boiling or around the boiling point of 212 degrees

 

Pictures:

1 - Temping warm water before boiling

1 - Cold water at 5 minutes

1 - Hot water boiling at 10 minutes

1 - Cold water boiling at 15 minutes

2 - Hot water temps before boiling

2 - Hot water boiling at 9 minutes

2 - Cold water temps before boiling

2 - Cold water boiling at 13 minutes

3 - Hot water before boiling

3 - Cold water before boiling

3 - Hot water boiling after 10 minutes

3 - Cold water boiling after 14 minutes

Data:

Controlled Variables: 
 1. Same pans used to boil hot and cold water
 2. Amount of water used was same for hot and cold water (6 cups)
 3. Same temperature setting used to boil water on the same stove (8)
 4. Same time interval used between recordings (5 minutes)
 5. Same thermometer used to record temperatures

Formulated Theory:

Hot water boils faster because the water molecules are already moving faster and are already closer to the boiling point of water. The cold water on the other hand takes a little bit longer to boil because it needs to warm the water throughout, whereas the warm water is already warm.  

Average values of repeated experiment:

 After repeating the experiment three different times, it allowed me to obtain an average time that it takes both hot and cold water to boil. If I had only done this experiment one time, the data shown would not be useful because it would only show what happened once and not an average of what happens multiple times. My average boil time for hot water was 9.33 minutes, while my average boil time for cold water was 14 minutes, backing up my hypothesis and formulated theory.

3. Does salt water freeze faster or slower than regular water?

Hypothesis: I think that the regular water is going to freeze faster, while the salt water is just going to get colder. The salt water isn't going to freeze because the salt crystals are going to prevent the water from freezing over due to the fact that salt melts ice.

 
Materials: 
 1. Two - 18oz plastic cups
 2.  Measuring cup
 3. Thermometer
 4. Water
 5. Salt
 5. Freezer
 6. Timer
 7. Labels

Setup:

 1. Fill the cups with 1 cup of water

 2. Add 1 teaspoon of salt into one of the cups and both cups accordingly

 3. Record temperatures of both the regular water and the salt water.

 3. Place both containers into the freezer on level surface. 

 4. After 30 minutes, record the temperatures of both regular water and salt water. 

 5. After 30 minutes, record temperatures again for both cups

 6. Repeat process until water is completely frozen.   

Pictures:

1 - Taking Temperatures before

1 - Putting both cups in freezer

1 - Taking temps at 90 minutes

1 - Cups at 90 minutes

2 -Adding 1 teaspoon of salt to one cup

2 - Putting both cups in freezer

2 - After 90 minutes

2 - Regular frozen and salt is slushier

3 - Taking temps before freezing

3 - Placing into the freezer

3 - Taking temps at 90 minutes

3 - Regular frozen at 180 minutes

Data: 

Controlled Variables: 

1. Exact same cups for both hot and cold water (18oz plastic cups)

 2. Amount of water used for both hot and cold water (1 cup each)

 3. Same freezer used

 4. Same time intervals between temperature recordings (30 minutes)

 5. Same thermometer used to record temperatures

 6. Amount of salt used in salt water cup

Formulated Theory:

 I was able to prove that regular waters freezes much faster then water with salt added to it. he regular water froze faster because it didn't have the salt crystals to line up and try to slow down and freeze. The salt also drastically slowed down the freezing process because salt breaks down ice crystals, which is also why the water was able to drop below the freeze point without completely freezing. 

Average values of repeated experiment:

After conducting this experiment three different times, I was able to calculate an average freeze rate for regular water and for salt water. Had I only conducted this experiment once, I wouldn't have been able to find an average and would of only had one time worth of information which wouldn't really be useful because it could have been a fluke. The average time it took to freeze regular water was about 180 minutes, while the salt water was still a little bit slushie after 210 minutes.

Applying Concepts

Atoms of Water (H20):

Video Animation of Water Molecules in 3 States of Matter:

Solid Form - organized

Liquid Form - slowly moving

Gas Form - moving fast and spread out

Solid to Gas Video - http://www.edumedia-sciences.com/en/a618-3-states-of-water  

Three states video -  http://www.youtube.com/watch?v=s-KvoVzukHo

Connections to Real World Application:

       Even though this experiment seems easy enough and somewhat meaningless, it covers many different science concepts. First of all, we have to conduct our own experiments, which include hypothesizes, the actual experiments, variables, scientific models, and formulated theories. Secondly, we are working with water molecules and the three forms of it's matter: solid, liquid, and gas. Thirdly, we are working with compounds when we mixed the salt and water together. Lastly, we also learned about physical changes when we froze the water.

      Conducting these experiments was a nice review of what I had learned in high school and it never hurts to relearn something. In the experiment I came to the conclusion that hot water freezes faster then cold water and also boils faster then cold water. Even though most people would say that hot water would not freeze faster, it in fact does because cold water forms ice crystals at the top of the water drastically slowing the freezing process, where as the hot water form these ice crystals throughout the water causing a more even freezing process. Boiling wise, common sense kicks in and is right by saying that hot water boils much fast because it is already close to boiling point and the water molecules are already moving faster. Lastly, I came up with the conclusion that regular water freezes much faster then salt water because salt slows down the freezing process of water, causing it to take much, much longer then regular water.

     Now that I conducted these experiments, I can use my knowledge in my everyday life. For instance, if I need to make a lot of ice in a shorter time span, I'll just use hot water to speed up the process. Same goes for boiling water, if I need to boil water faster I will just use hotter water instead of cold water. Lastly, I know that if I don't want water to freeze to add some salt and this is also why we use salt on our sidewalks and streets in winter. These three concepts may seem like common sense, but they always aren't, yet they are very useful to most people to know. So in a way, experiments that may seem boring and pointless, can show the most interesting results that may come in handy in everyday life.