Scientific Method and States of Matter

Activity 1

The first activity performed was in regards to the states of matter: solid, liquid, and gas. The questions to answer included:

• Does hot water or cold water freeze faster?
• Does hot water or cold water boil faster?
• Does salt water freeze faster or slower than regular water?

Hypothesis

I think that the cold water will freeze faster and the hot water will boil faster because it takes less energy to reach a boiling/freezing point when the water is closer to that point compared to further away. Also, I think the salt water will not freeze as fast as normal water because the salt will prevent the ice from forming at the regular freezing point. This is why salt is put on roads in the winter in order to prevent icy conditions.

Controlled Variables

• Water temperature
• Amount of water
• Amount of salt

Does hot water or cold water freeze faster?

In this experiment, the results proved my hypothesis when the cold water froze faster in all 3 trials.

Time it took for water to freeze	Hot Water	Cold Water
	24 minutes	10 minutes
	24 minutes	12 minutes
	26 minutes	12 minutes

I added a 1/2 cup of water in each small bowl. 1 bowl contained refrigerated water while the other bowl contained boiling water. Using the wonderful Wisconsin weather, mother nature froze the water for me at -11 degrees. I checked the bowls every couple minutes to see if the surface of the water was frozen. In every trial, the cold water froze faster which supports my hypothesis.

After the first trial, I decided not to refrigerate the bowl with the water because this made a 2 minute difference of a freezing point. On the third trial, the water was boiling for a longer time which accounts for the added 2 minutes of the hot water. Other than these differences, the repeatability of the experiment appears to be very easy. The average values are: 24.7 minutes (hot water) and 11.3 minutes (cold water).

Does hot water or cold water boil faster?

My hypothesis was correct in this experiment as well. The hot water boiled faster than the cold water.

Time it took for water to boil	Hot Water	Cold Water
	3 minutes	5 minutes
	2 ½ minutes	5 minutes
	3 minutes	5 minutes

Using steaming water from the sink compared to water in the fridge, the hot water boiled faster in all 3 trials. Once the burner was up to the full temperature with the pot on it, I put the water in the pot. I tested only 1 temperature of water at a time in order to keep the surface area consistent. This experiment was quicker than freezing water because I had access to extreme heat and not extreme cold. The repeatability of this experiment is also very easy because there are not many variables and they can all be controlled. The average values are: 2.8 min (hot) and 5 min (cold).

Does salt water freeze faster or slower than regular water?

This experiment was the most fun because I wasn't sure what to expect. The results I recorded supported my hypothesis when the regular water froze faster than the salt water. Interestingly, the salt water never really froze. It just turned to slush! This explains why the roads are always full of disgusting slush during the winter.
During this experiment, the temperature outside was 1 degree and I let the bowls of water sit outside for 1 hour. For the first attempt, I only added 1/4 of a tbsp of salt into the water which essentially did nothing. On the second attempt, I added 1 tbsp of salt which never became fully saturated in the water. As you can see on the left, the left bowl is not clear because of the salt mixed with the water. This was taken after the experiment. The salt affected the water and delayed the formation of ice as well as hindered its formation. The salt water never fully took a solid form.

Time it took for water to freeze	Salt Water	Normal Water
	25 minutes (1/4 tbsp of salt)	22 minutes
	32 minutes (1 tbsp of salt)	22 minutes
	31 minutes (1 tbsp of salt)	22 minutes

With the correct measuring tools, the repeatability of this experiment can be easy. The accuracy of the trials were fairly consistent despite the varying amount of salt added to the water. In the end, the salt kept the water from freezing solid like the normal water did. As you can see on the right, the normal water took a fully solid form and was able to be held upside down while keeping its shape. The average values for this experiment are: 29.3 minutes (salt water) and 22 minutes (normal water).

**In order to make the experiments more consistent, I could have used distilled water instead of sink water. Another change would be to use a thermometer to determine the exact time that the water reached the boiling or freezing point.

*Click on text below to view video*

Water molecules can be arranged in the three states of matter shown in this video. Solid water, or ice, occurs at a temperature below 32 degrees F. The molecules move close together to form a definite shape. Liquid water is formed at a normal temperature in order for it to flow. It has a definite volume but not a definite shape. The third state that water can take, gas, occurs above the boiling point of water which is 212 degrees F. It can also occur at a regular temperature too. The water in puddles can evaporate slowly over time.

This image of a single water molecule shows the elements involved. 1 oxygen atom has 2 free valence electron spots. Because hydrogen atoms have only 1 electron, a pair of hydrogen atoms can easily bond with an oxygen atom to create a water molecule.

Formulated Theory

My theory that answers the questions posed is this: pure water consistently freezes and boils at the same rate. If the water is already warm, it will boil faster and freeze slower. If the water is already cold, it will freeze faster and boil slower. If salt is added to water, it will freeze slower. The temperature of water determines the time in which it will reach the freezing/ boiling point. Warmer water has more energy while cold water has less energy, so the warm water took longer to reach a level of less energy while the cold water also took longer to reach a level of higher energy.

Scientific Method

The first part of the scientific method is observation and asking questions. Observation of water in a cold temperature allowed the questions arise. The questions posed were regarding the states of matter. The next step is to create a hypothesis. I did this when I said that the cold water would freeze faster, hot water would boil faster, and normal water would freeze faster. To test the hypothesis, the next step is conduct the experiment. I did this through my simple procedure. Analyzing the data and drawing conclusions comes after the experiment. My data and conclusions correlated with the already discovered states of matter. Finally, the groundbreaking discovery can be formulated into a theory or a law by which everything consistently occurs.

Conclusion

The science concepts explored are important to understand. The scientific method must be followed in order to perform successful experiments and findings. The states of matter are also a key concept to grasp. Atoms tend to group closer together in cold conditions which create solid objects with a definite shape and volume. When heated up, solid objects eventually melt and become free-flowing liquids without a definite shape. A liquid will take the shape of its container and still has a volume. When heated up intensely, the liquid will become a gas and evaporate into the air. Gases are unrestricted with no definite shape or volume, but they can be compressed.

The experiment I performed demonstrated these states of matter as well as a successful scientific method. I created a hypothesis based on questions and proved my hypothesis through the procedure. The cold water froze faster than the hot water, the hot water boiled faster than the cold water, and the normal water froze quicker than the salt water. My data for these experiments was consistent and correlated with the theory of the states of matter. As for the salt water, it did not freeze as quick because the mixture did not allow as much water to reach the surface. As a result the salt water did not freeze as a solid object but instead froze to create a slushy substance.

The scientific method allows modern concepts such as the law of gravity to be created and accepted. The duplication of experiments creates proof and backs up the original findings. The states of matter are also an important concept in our society. Water and ice are huge industries that people supply due to water being essential to survive. Water and ice covers most of our planet with oceans and lakes. Understanding the liquid, solid, and gas states of water can also be helpful for big reasons. With the Winter Olympics coming up, ice will play an important role in the games. Ice for hockey, luge, curling, and ice skating must be kept above a certain temperature in order to stay in its solid form. Snow can also be packed down into a sturdy solid to allow for maximum speed down slopes. The states of solid, liquid, and gas are very important to know and apply to real life.