1. What were the changes that you noticed?
Unfortunately, we were not able to complete this lab, therefore we could not analyze the different solutions to see any changes. When we boiled the 200 mL of water without salt, we obtained a boiling point of 99.8 degrees Celsius. Our boiling point was a very similar to our hypothesized boiling point of 100 degrees Celsius. We began the second step of adding salt
(NaCl) to our solution, however due to time constraint we had to stop in the middle of boiling our solution. We presume that the boiling point would increase from step one.
2. What were your results compared to the other groups?
In the first step of the lab, most groups had around the same boiling point between 95 and 100 degrees Celsius. As we continued the experiment many groups had a steady change in temperature, usually increasing a few degrees. However, there were one and two groups whose boiling points decreased or remained the same. This was interesting, as ideally, the boiling point should only increase a few degrees. There were many factors that determined the increases and decreases of temperature, such as amount of water added, NaCl added, and the boiling point of the solutions. Overall, most groups had a steady increase in temperature in each step of the experiment.
3. What were the relative differences?
Refer to question #2
4. What was the relative change in boiling point?
Our group did not reach this step in the lab due to time constraint. However, our hypothesis based on other groups' work would be that the temperature would increase a few degrees if we doubled the amount of solute. It would have been interesting to evaluate the changes in boiling point if we doubled the amount of solute.
Wednesday, April 29, 2009
Thursday, March 12, 2009
NaOH and HCl Lab
Jennifer Wilson
Chemistry 201-2
Mr. Schoudel
Given: 3M NaOH (aq) + 12M HCl (aq) → H2O + NaCl
How much water and how much salt?
Water: From the reaction
Introduction:
Our class has performed many interesting experiments, however we recently worked with dangerous acid and base solutions in an experiment to find the amount of water in a reaction. We were provided the equation above and the materials to accurately carry out the experiment. This experiment was very challenging, as we had to form our own methods and procedures. My partner, Samantha and I were unsure of how to approach the experiment, as we do not usually create our own procedures. We did have some knowledge of separating two aqueous solutions from an alcohol fermentation demonstration earlier in the year. While forming our own procedures was very challenging, it made us feel more in control of the experiment and at least for me, a closer connection to the lab. We did not have a set of directions; therefore we could alter our steps at any point during the procedure, which gave us more flexibility when finding the overall result. We made many revisions to our procedure, as the requirements for the experiment changed and we discovered new ways to reach the final result. After making these revisions, we finally devised a solid set of procedures that would hopefully lead us to the final result. Unlike past experiments that involved materials, such as water, sand or even a lollipop, we were using dangerous acid and base aqueous solutions. Although, we were nervous if we were forming the most accurate methods and did have a few mishaps here and there, our experiment was carried out well, which ultimately found us our unknown. This experiment was more challenging that usual labs, however the difficulty of the lab made it more interesting and informative.
Hypothesis:
We hypothesized that there would be a greater amount of water than salt, although we were not exactly positive why that would be the case. Furthermore, we believed that the solutions would be neutral when we first combined them, as we would measure the appropriate amounts. We knew that we had to boil the water out in order to find the amount of salt, and consequently, the amount of water. Additionally, we used the knowledge that we gained from the alcohol fermentation experiment that was demonstrated earlier in the year. From this experiment, we knew we needed to boil out one of the components in order to find the other. We made these hypotheses based on our knowledge of neutrality and stoichiometry.
Materials:
• NaOH
• HCl
• 2 small graduated cylinders
• 1 glass rod
• 2 100 mL beakers
• 1-2 pipettes
• 1 roll of paper towels
• 1 analytical balance
• 1-2 strips of pH paper
• Calculator
• Pencil
• Paper
• 1 Bunsen burner
• 1 stand
• 1 wire mesh square
• 1 starter/lighter
• 1 crucible and top
• Clock
• Baking soda
• Vinegar
• 1 pair of tongs
• 1 clear, plastic tray
Procedure:
1.Gather all supplies and materials necessary for the experiment.
2. Measure out 4 mL of the 3M NaOH and 1 mL of the 12M HCl into separate graduated cylinders. However, finding these precise measurement will be very difficult. To make this process easier, pour around 10 mL of each solution into a separate beaker. To make sure that the solution does not run down the side of the container, place a glass rod in the center of the beaker. Using a pipette, drop the correct amount of acid or base into the graduated cylinder. For the HCl, be sure to measure it out under the hood, as it will produce a cloud.
3. Find the mass of a 100 mL empty beaker. Record this number.
4. Pour the two solutions into the beaker. Using the glass rod, place a drop of the solution onto the pH paper. If the pH paper does not turn green, add the necessary amounts of acid or base. Record all information.
5. Using a pipette and an analytical balance, find the mass of one drop from the pipette. Take more than one sample and then calculate the average. Using the density formula, determine the volume of one drop.
6. Find the mass of the beaker. Find the mass of the solution. Record all information.
7. Set up the burner and all necessary materials for the later step.
8. Place the empty crucible on top of the burner and allow the flame to pass over it for 5 minutes. This will purify the crucible. Allow the crucible to cool for around 2-3 minutes.
9. Find the mass of the empty crucible.
10. Pour the neutral solution into the crucible.
11. Using a burner, place the crucible above the flame. Pass the flame gently over the crucible. Check the amount of water every minute or so to see how much water is left. When there is only white salt and no water left, turn the burner off. This will eventually evaporate the water out, leaving only the salt. Allow the crucible to cool.
12. Find the mass of the salt by finding the mass of the crucible. Record these results.
13. Subtract the amount of salt from the total mass. This will give you the amount of water.
14. Record your results and data.
15. Clean up all materials and workspace. When pouring out the solutions, you must neutralize them. For the acid solution, or HCl, pour a little bit of baking soda into the graduated cylinder/beaker. For the base solution, or NaOH, pour a little bit of vinegar into the graduated cylinder/beaker. This will neutralize the solutions and make them safe to go down the drain.
*If you are not completing your experiment in one sitting, cover the acid and base to ensure accurate results.
Data/Results:
# Of drops of acid Added 2 drops Added 5 drops Added 10 drops Added 0 drops
# Of drops of base Added 0 drops Added 0 drops Added 0 drops Added 3 drops
Color/Is it neutral? Dark blue= too basic Blue= too basic Red= too acidic Light green= neutral
*Note: These numbers were the amounts added we realized that the initial solution was not neutral. This is the amount of acid/base that we added to the first solution.
Mass of drops:
(1 drop) 0.0207 grams
(2 drops) 0.0341 grams
(3 drops) 0.0648 grams
(4 drops) 0.0889 grams
Average mass of 1 drop: 0. 0112 grams
Density=Mass/Volume
Density of water=1
Mass of drop=0.0112
1=0.0112/V
V= 0.0112 mL (1 drop)
Mass of empty graduated cylinder=25.93 g
Mass of empty beaker=50.83 g
Mass of beaker with neutral solution=56.0763 g
Mass of solution=56.0763-50.83=5.2463 g
Mass of empty crucible=15.5217 g
Mass of crucible after heating=15.8483 g
Amount of NaOH used=0.0121 moles=0.48 g
- 3M=moles/L
- 0.0112 x 3=0.0336 grams
- 4 mL + 0.0336=4.0336
- 4.0336/1000=0.0040336 L
- 3M=moles/0.0040336
- Moles=0.0121
- 0.0121 x 40=0. 48 g
Amount of HCl used=0.014 moles= 0.52 g
- 12M=moles/L
- 0.0112 x 17=0.1904 g
- 1 mL + 0.1904=1.1904
- 1.1904/1000=0.0011904 L
- 12M=moles/0.0011904
- Moles=0.014
- 0.014 x 36.458=0.52 g
Mass of NaCl at the end of the experiment=15.8483-15.5217=0.3266 g
0.3266 g/58.44=0.006 moles
Mass of H2O at the end of the experiment=5.2463-0.3266=4.92 g
4.92 g/ 20.16= 0.24 moles
Actual/Theoretical Yield:
Theoretical Yield= 3M NaOH + 12M HCl --> NaOH + H2O
Concentration= Mol/Volume
Mol= CV
HCl (12M)(0.001)= 0.012 Mol
NaOH (3M)(0.004)= 0.012 Mol
Mol --> Grams
0.012 Mol NaOH x 58.44 g/ 1 Mol NaOH = 0.7 g (Under perfect conditions)
% Yield= Actual/ Theoretical x 100
0.3266 g/ 0.7 g x 100 = 46.66 %
0.3266 g= Experimental Yield
Discussion/Analysis:
We hypothesized that there would be a greater amount of water than salt, although we were not exactly positive why that would be the case. Furthermore, we believed that the solutions would be neutral when we first combine them, as we would measure the appropriate amounts. We knew that we had to boil the water out in order to find the amount of salt, and consequently, the amount of water. We knew we needed to boil out one of the components in order to find the other. This was a step in the right direction, however I believe we made it more complicated than the experiment actually was. It was difficult to know if we were actually in the right direction because we had devised our own procedures that could possibly result in something very dangerous. Fortunately, everyone was safe and productive during this experiment, so that no group had any accidents with an acid or base solution. During our experiment we reached the point were we had to test if our solution was neutral. We used pH paper to determine the neutrality of the solution. On our first attempt, we were left with a blue drop on the paper, which signified that the solution was too basic. Therefore we added five more drops of acid, which formed another blue drop on the opposite side of the paper. We rushed the next step in our experiment and added ten drops of acid to reach a reddish dye on the paper. Now the solution was too acidic. Next time I think it is important that if we find ourselves frustrated that the solution is not changing, we add smaller amounts of the necessary acid or base, therefore we are more efficient. We finally added three more drops of base to finally neutralize our solution. We continued with our experiment and made many measurements and weight calculations to help determine our final mass of water in the reaction. Something to remember for next experiment is to work efficiently, but neatly as well. I think it would have helped our group if we worked at a more rapid pace, yet still maintained the neatness and accuracy when making measurements and calculations.
Conclusion:
The NaOH and HCl lab was a new and informative way of learning about neutrality and stoichiometry. The lab was different in the sense that we had to devise our own procedures and follow our methods, even if they were not accurate. This was one of the major challenges that my group had while performing this experiment. We were unsure if we were accurately testing the amount of water remaining in the reaction. Although this was a large obstacle to overcome right from the start of the experiment, we made some very tactful decisions and measurements that helped us to form our final answer. Furthermore, the materials and information given was very limited which made this experiment even more challenging. Once we reached the point that we knew our procedures were somewhat correct, we began to relax and try to carry out the experiment as efficiently as possible. With the exception of a few mishaps, Sam and I were able to follow through with our experiment to find what we hope to be the most accurate answer. This experiment was different from other experiments, as I felt we were more flexible with the procedures and could determine the results with our methods. I enjoyed the opportunity to devise our own procedures and follow through with an interesting experiment.
Chemistry 201-2
Mr. Schoudel
Given: 3M NaOH (aq) + 12M HCl (aq) → H2O + NaCl
How much water and how much salt?
Water: From the reaction
Introduction:
Our class has performed many interesting experiments, however we recently worked with dangerous acid and base solutions in an experiment to find the amount of water in a reaction. We were provided the equation above and the materials to accurately carry out the experiment. This experiment was very challenging, as we had to form our own methods and procedures. My partner, Samantha and I were unsure of how to approach the experiment, as we do not usually create our own procedures. We did have some knowledge of separating two aqueous solutions from an alcohol fermentation demonstration earlier in the year. While forming our own procedures was very challenging, it made us feel more in control of the experiment and at least for me, a closer connection to the lab. We did not have a set of directions; therefore we could alter our steps at any point during the procedure, which gave us more flexibility when finding the overall result. We made many revisions to our procedure, as the requirements for the experiment changed and we discovered new ways to reach the final result. After making these revisions, we finally devised a solid set of procedures that would hopefully lead us to the final result. Unlike past experiments that involved materials, such as water, sand or even a lollipop, we were using dangerous acid and base aqueous solutions. Although, we were nervous if we were forming the most accurate methods and did have a few mishaps here and there, our experiment was carried out well, which ultimately found us our unknown. This experiment was more challenging that usual labs, however the difficulty of the lab made it more interesting and informative.
Hypothesis:
We hypothesized that there would be a greater amount of water than salt, although we were not exactly positive why that would be the case. Furthermore, we believed that the solutions would be neutral when we first combined them, as we would measure the appropriate amounts. We knew that we had to boil the water out in order to find the amount of salt, and consequently, the amount of water. Additionally, we used the knowledge that we gained from the alcohol fermentation experiment that was demonstrated earlier in the year. From this experiment, we knew we needed to boil out one of the components in order to find the other. We made these hypotheses based on our knowledge of neutrality and stoichiometry.
Materials:
• NaOH
• HCl
• 2 small graduated cylinders
• 1 glass rod
• 2 100 mL beakers
• 1-2 pipettes
• 1 roll of paper towels
• 1 analytical balance
• 1-2 strips of pH paper
• Calculator
• Pencil
• Paper
• 1 Bunsen burner
• 1 stand
• 1 wire mesh square
• 1 starter/lighter
• 1 crucible and top
• Clock
• Baking soda
• Vinegar
• 1 pair of tongs
• 1 clear, plastic tray
Procedure:
1.Gather all supplies and materials necessary for the experiment.
2. Measure out 4 mL of the 3M NaOH and 1 mL of the 12M HCl into separate graduated cylinders. However, finding these precise measurement will be very difficult. To make this process easier, pour around 10 mL of each solution into a separate beaker. To make sure that the solution does not run down the side of the container, place a glass rod in the center of the beaker. Using a pipette, drop the correct amount of acid or base into the graduated cylinder. For the HCl, be sure to measure it out under the hood, as it will produce a cloud.
3. Find the mass of a 100 mL empty beaker. Record this number.
4. Pour the two solutions into the beaker. Using the glass rod, place a drop of the solution onto the pH paper. If the pH paper does not turn green, add the necessary amounts of acid or base. Record all information.
5. Using a pipette and an analytical balance, find the mass of one drop from the pipette. Take more than one sample and then calculate the average. Using the density formula, determine the volume of one drop.
6. Find the mass of the beaker. Find the mass of the solution. Record all information.
7. Set up the burner and all necessary materials for the later step.
8. Place the empty crucible on top of the burner and allow the flame to pass over it for 5 minutes. This will purify the crucible. Allow the crucible to cool for around 2-3 minutes.
9. Find the mass of the empty crucible.
10. Pour the neutral solution into the crucible.
11. Using a burner, place the crucible above the flame. Pass the flame gently over the crucible. Check the amount of water every minute or so to see how much water is left. When there is only white salt and no water left, turn the burner off. This will eventually evaporate the water out, leaving only the salt. Allow the crucible to cool.
12. Find the mass of the salt by finding the mass of the crucible. Record these results.
13. Subtract the amount of salt from the total mass. This will give you the amount of water.
14. Record your results and data.
15. Clean up all materials and workspace. When pouring out the solutions, you must neutralize them. For the acid solution, or HCl, pour a little bit of baking soda into the graduated cylinder/beaker. For the base solution, or NaOH, pour a little bit of vinegar into the graduated cylinder/beaker. This will neutralize the solutions and make them safe to go down the drain.
*If you are not completing your experiment in one sitting, cover the acid and base to ensure accurate results.
Data/Results:
# Of drops of acid Added 2 drops Added 5 drops Added 10 drops Added 0 drops
# Of drops of base Added 0 drops Added 0 drops Added 0 drops Added 3 drops
Color/Is it neutral? Dark blue= too basic Blue= too basic Red= too acidic Light green= neutral
*Note: These numbers were the amounts added we realized that the initial solution was not neutral. This is the amount of acid/base that we added to the first solution.
Mass of drops:
(1 drop) 0.0207 grams
(2 drops) 0.0341 grams
(3 drops) 0.0648 grams
(4 drops) 0.0889 grams
Average mass of 1 drop: 0. 0112 grams
Density=Mass/Volume
Density of water=1
Mass of drop=0.0112
1=0.0112/V
V= 0.0112 mL (1 drop)
Mass of empty graduated cylinder=25.93 g
Mass of empty beaker=50.83 g
Mass of beaker with neutral solution=56.0763 g
Mass of solution=56.0763-50.83=5.2463 g
Mass of empty crucible=15.5217 g
Mass of crucible after heating=15.8483 g
Amount of NaOH used=0.0121 moles=0.48 g
- 3M=moles/L
- 0.0112 x 3=0.0336 grams
- 4 mL + 0.0336=4.0336
- 4.0336/1000=0.0040336 L
- 3M=moles/0.0040336
- Moles=0.0121
- 0.0121 x 40=0. 48 g
Amount of HCl used=0.014 moles= 0.52 g
- 12M=moles/L
- 0.0112 x 17=0.1904 g
- 1 mL + 0.1904=1.1904
- 1.1904/1000=0.0011904 L
- 12M=moles/0.0011904
- Moles=0.014
- 0.014 x 36.458=0.52 g
Mass of NaCl at the end of the experiment=15.8483-15.5217=0.3266 g
0.3266 g/58.44=0.006 moles
Mass of H2O at the end of the experiment=5.2463-0.3266=4.92 g
4.92 g/ 20.16= 0.24 moles
Actual/Theoretical Yield:
Theoretical Yield= 3M NaOH + 12M HCl --> NaOH + H2O
Concentration= Mol/Volume
Mol= CV
HCl (12M)(0.001)= 0.012 Mol
NaOH (3M)(0.004)= 0.012 Mol
Mol --> Grams
0.012 Mol NaOH x 58.44 g/ 1 Mol NaOH = 0.7 g (Under perfect conditions)
% Yield= Actual/ Theoretical x 100
0.3266 g/ 0.7 g x 100 = 46.66 %
0.3266 g= Experimental Yield
Discussion/Analysis:
We hypothesized that there would be a greater amount of water than salt, although we were not exactly positive why that would be the case. Furthermore, we believed that the solutions would be neutral when we first combine them, as we would measure the appropriate amounts. We knew that we had to boil the water out in order to find the amount of salt, and consequently, the amount of water. We knew we needed to boil out one of the components in order to find the other. This was a step in the right direction, however I believe we made it more complicated than the experiment actually was. It was difficult to know if we were actually in the right direction because we had devised our own procedures that could possibly result in something very dangerous. Fortunately, everyone was safe and productive during this experiment, so that no group had any accidents with an acid or base solution. During our experiment we reached the point were we had to test if our solution was neutral. We used pH paper to determine the neutrality of the solution. On our first attempt, we were left with a blue drop on the paper, which signified that the solution was too basic. Therefore we added five more drops of acid, which formed another blue drop on the opposite side of the paper. We rushed the next step in our experiment and added ten drops of acid to reach a reddish dye on the paper. Now the solution was too acidic. Next time I think it is important that if we find ourselves frustrated that the solution is not changing, we add smaller amounts of the necessary acid or base, therefore we are more efficient. We finally added three more drops of base to finally neutralize our solution. We continued with our experiment and made many measurements and weight calculations to help determine our final mass of water in the reaction. Something to remember for next experiment is to work efficiently, but neatly as well. I think it would have helped our group if we worked at a more rapid pace, yet still maintained the neatness and accuracy when making measurements and calculations.
Conclusion:
The NaOH and HCl lab was a new and informative way of learning about neutrality and stoichiometry. The lab was different in the sense that we had to devise our own procedures and follow our methods, even if they were not accurate. This was one of the major challenges that my group had while performing this experiment. We were unsure if we were accurately testing the amount of water remaining in the reaction. Although this was a large obstacle to overcome right from the start of the experiment, we made some very tactful decisions and measurements that helped us to form our final answer. Furthermore, the materials and information given was very limited which made this experiment even more challenging. Once we reached the point that we knew our procedures were somewhat correct, we began to relax and try to carry out the experiment as efficiently as possible. With the exception of a few mishaps, Sam and I were able to follow through with our experiment to find what we hope to be the most accurate answer. This experiment was different from other experiments, as I felt we were more flexible with the procedures and could determine the results with our methods. I enjoyed the opportunity to devise our own procedures and follow through with an interesting experiment.
Tuesday, March 3, 2009
Lab Procedure
Jennifer Wilson
Chemistry 201-2
3/3/09
Given: 6M NaOH (aq) + 12M HCl (aq) → H2O + NaCl
How much water and how much salt?
Water:
1. From the reaction
2. From the reactants, already have the water
Procedure
1. Measure out 50 mL of the 6M NaOH and 100 mL of the 12M HCl in a graduated cylinder.
2. Find the mass of two empty Erlenmeyer flasks. Record these amounts. Label the Erlenmeyer flasks.
3. Pour the 50 mL of the NaOH solution into the Erlenmeyer flasks.
4. Find the mass of the solution. Record this amount.
5. Using a hot plate or a burner, place the Erlenmeyer flask full of the NaOH solution above the flame. This will eventually evaporate the water, leaving only the NaOH.
6. Find the mass of the NaOH. Record these results.
7. Subtract the mass of the NaOH from the mass that was found in step 4. This will give you the amount of water that is in the solution.
8. Repeat steps 3-7 with the HCl solution.
9. Repeat step 1.
10. Pour the two solutions into another Erlenmeyer flask. Shake until dissolved.
11. Find the mass of the solution.
12. Using a hot plate or a burner, place the Erlenmeyer flask above the flame. This will eventually evaporate the water out, leaving only the salt.
13. Find the mass of the salt. Record these results.
14. Subtract the amount of salt from the total mass. This will give you the amount of water.
15. Record your results and data.
Chemistry 201-2
3/3/09
Given: 6M NaOH (aq) + 12M HCl (aq) → H2O + NaCl
How much water and how much salt?
Water:
1. From the reaction
2. From the reactants, already have the water
Procedure
1. Measure out 50 mL of the 6M NaOH and 100 mL of the 12M HCl in a graduated cylinder.
2. Find the mass of two empty Erlenmeyer flasks. Record these amounts. Label the Erlenmeyer flasks.
3. Pour the 50 mL of the NaOH solution into the Erlenmeyer flasks.
4. Find the mass of the solution. Record this amount.
5. Using a hot plate or a burner, place the Erlenmeyer flask full of the NaOH solution above the flame. This will eventually evaporate the water, leaving only the NaOH.
6. Find the mass of the NaOH. Record these results.
7. Subtract the mass of the NaOH from the mass that was found in step 4. This will give you the amount of water that is in the solution.
8. Repeat steps 3-7 with the HCl solution.
9. Repeat step 1.
10. Pour the two solutions into another Erlenmeyer flask. Shake until dissolved.
11. Find the mass of the solution.
12. Using a hot plate or a burner, place the Erlenmeyer flask above the flame. This will eventually evaporate the water out, leaving only the salt.
13. Find the mass of the salt. Record these results.
14. Subtract the amount of salt from the total mass. This will give you the amount of water.
15. Record your results and data.
Wednesday, September 24, 2008
Density Lab Report
Jennifer Wilson
9/24/08
Chemistry 201-2
Mr. Schoudel
Introduction:
In science there are several questions that require experiments and tests to discover and understand the result. Our class recently discussed density, mass, and volume. All three of these components were key in solving our scientific question. Our experiment was to find the most accurate way for a vial to float into two different types of water, with different densities. The two types of waters consisted of warm fresh water and cold salt water. The water was poured into a fish tank, with blue die in the warm fresh water, displaying the two layers of water. We were given the information that the density of the warm fresh water was greater than 1.00 g/cm3 and the density of the bottom layer was less than 1.00 g/cm3. When my partner, Lucy and I first heard about this experiment, we did not know how to approach it. We went through a long process of brainstorming ideas about how to find an accurate way to approach this question. Our first thoughts were to put some type of weight in the vial to allow it to sink when placed in the water. We thought that putting boiling water or freezing water in the vial, would add weight to the vial, causing it to sink. We were not sure if this was at all accurate, which is why this experiment was so challenging for us.
In addition, it was almost like trial and error, until we observed our materials and the question, which lead us to a more accurate procedure. We were correct about putting weight in the vial, however water was maybe not the most accurate object to add weight with. We also observed the density formula; Density = Mass/Volume. This gave us the idea that we could find the density of the vial, and as a result the vial would float in the middle of the two waters. Our goal was to make the mass of the vial the same as the volume. This helped our process to become more accurate and answered several of our questions.
Hypothesis:
Our hypothesis is to place a type of weight in the vial; therefore the vial will float in the middle of the two types of water. Our initial weight was more water, however as the lab progressed, we decided that we would try to add a different weight, such as sand or table salt.
Materials:
• One large fish tank
• One small plastic vial
• Warm fresh water
• Cold salt water
• Sand
• Density Formula: Density → Mass/Volume
• Small (most accurate) graduated cylinder
• Analytical scale
• Pencil and pen to record data and results
Methods:
• Record initial mass of the vial
• Put water in graduated cylinder to determine volume (fill to 60 ml mark)
• Put water in vial (Fill to the top)
• Test the volume of the vial
• Record the mass of the vial with sand
• Test the experiment
• If it does not succeed, then keep adding or subtracting weight from the vial
• Also continue to test the weight of the vial each time, therefore your result is more accurate
Data/Results:
Test # 1 X
Total Mass: 24 grams + weight of vial = approx. 28- 30 grams
Result: Sunk to the bottom of the tank
Test # 2 X
Total Mass: 29. 457 grams
Result: Sunk to the bottom of the tank
Test # 3 X
Total Mass:
22.2 grams
Result: Float/ Remained a little above water
Test # 4 X
Total Mass: 24.28 grams
Result: The vial remained at the top of the water
Test # 5 +
Total Mass: 25.2 grams
Result: The vial remained in the middle of the two waters
Discussion/ Analysis:
Our hypothesis for this experiment was to put some type of weight in the vial; therefore the vial could float in the middle of the two types of water. This was a step in the right direction because it was important to add more weight to the vial, to successfully carry out the experiment. As the experiment progressed we noticed that adding sand to the vial would add weight and therefore would make our experiment accurate. We had a lot of difficulty discovering the correct amount of sand because we had to observe the density formula as we were adding or subtracting weight from the vial. The volume of our vial was 24 ml and we had to make the mass 24 as well because we need to balance out the density, which was 1 ml. This does not seem very difficult, however you had to remember that the vial also weighed something; therefore we had to consider this and adjust our experiment to this weight. Furthermore, each attempt to sink the vial low enough to float in the middle, was closer and closer. With out first attempt, we forgot to subtract the weight of vial, therefore making the vial too heavy and sinking right down to the bottom. On our next tries we either added to much sand or subtracted too much sand, making this a very repetitive process. Although this was quite repetitive, it made us observe every step of our experiment to make sure it was the most accurate we could make it.
In addition, one thing that could have made our experiment more accurate was taking our time with each step. I think the reason we had so many attempts was because we sometimes were so anxious and excited about testing the vial, we would remove too much weight, add too much, etc. These were key elements in having a successful experiment. Although we rushed our experiment as it became more exciting and interesting, we enjoyed each step of the process.
Conclusion:
The vial lab was a fun and interesting way to introduce the density formula. This lab was not very obvious; therefore it took all the groups time to create a valid hypothesis and experiment. My partner and I struggled in the beginning of the lab because we were both unsure at how to approach the lab. However, as we looked at our materials and information, we were able to unfold the key points that were essential to a successful experiment. Even given the density formula, it was still not an easy task. Furthermore, this lab was very frustrating, as we became closer and closer to our final answer. Each step was so close, yet so far. We either needed to at more weight or subtract weight; it was not a simple job. In addition, we were also very nervous with each step because we were sometimes unsure of the result. Finally, this was an interesting and challenging experiment, however we learned to take our time and try to be as accurate as possible.
9/24/08
Chemistry 201-2
Mr. Schoudel
Introduction:
In science there are several questions that require experiments and tests to discover and understand the result. Our class recently discussed density, mass, and volume. All three of these components were key in solving our scientific question. Our experiment was to find the most accurate way for a vial to float into two different types of water, with different densities. The two types of waters consisted of warm fresh water and cold salt water. The water was poured into a fish tank, with blue die in the warm fresh water, displaying the two layers of water. We were given the information that the density of the warm fresh water was greater than 1.00 g/cm3 and the density of the bottom layer was less than 1.00 g/cm3. When my partner, Lucy and I first heard about this experiment, we did not know how to approach it. We went through a long process of brainstorming ideas about how to find an accurate way to approach this question. Our first thoughts were to put some type of weight in the vial to allow it to sink when placed in the water. We thought that putting boiling water or freezing water in the vial, would add weight to the vial, causing it to sink. We were not sure if this was at all accurate, which is why this experiment was so challenging for us.
In addition, it was almost like trial and error, until we observed our materials and the question, which lead us to a more accurate procedure. We were correct about putting weight in the vial, however water was maybe not the most accurate object to add weight with. We also observed the density formula; Density = Mass/Volume. This gave us the idea that we could find the density of the vial, and as a result the vial would float in the middle of the two waters. Our goal was to make the mass of the vial the same as the volume. This helped our process to become more accurate and answered several of our questions.
Hypothesis:
Our hypothesis is to place a type of weight in the vial; therefore the vial will float in the middle of the two types of water. Our initial weight was more water, however as the lab progressed, we decided that we would try to add a different weight, such as sand or table salt.
Materials:
• One large fish tank
• One small plastic vial
• Warm fresh water
• Cold salt water
• Sand
• Density Formula: Density → Mass/Volume
• Small (most accurate) graduated cylinder
• Analytical scale
• Pencil and pen to record data and results
Methods:
• Record initial mass of the vial
• Put water in graduated cylinder to determine volume (fill to 60 ml mark)
• Put water in vial (Fill to the top)
• Test the volume of the vial
• Record the mass of the vial with sand
• Test the experiment
• If it does not succeed, then keep adding or subtracting weight from the vial
• Also continue to test the weight of the vial each time, therefore your result is more accurate
Data/Results:
Test # 1 X
Total Mass: 24 grams + weight of vial = approx. 28- 30 grams
Result: Sunk to the bottom of the tank
Test # 2 X
Total Mass: 29. 457 grams
Result: Sunk to the bottom of the tank
Test # 3 X
Total Mass:
22.2 grams
Result: Float/ Remained a little above water
Test # 4 X
Total Mass: 24.28 grams
Result: The vial remained at the top of the water
Test # 5 +
Total Mass: 25.2 grams
Result: The vial remained in the middle of the two waters
Discussion/ Analysis:
Our hypothesis for this experiment was to put some type of weight in the vial; therefore the vial could float in the middle of the two types of water. This was a step in the right direction because it was important to add more weight to the vial, to successfully carry out the experiment. As the experiment progressed we noticed that adding sand to the vial would add weight and therefore would make our experiment accurate. We had a lot of difficulty discovering the correct amount of sand because we had to observe the density formula as we were adding or subtracting weight from the vial. The volume of our vial was 24 ml and we had to make the mass 24 as well because we need to balance out the density, which was 1 ml. This does not seem very difficult, however you had to remember that the vial also weighed something; therefore we had to consider this and adjust our experiment to this weight. Furthermore, each attempt to sink the vial low enough to float in the middle, was closer and closer. With out first attempt, we forgot to subtract the weight of vial, therefore making the vial too heavy and sinking right down to the bottom. On our next tries we either added to much sand or subtracted too much sand, making this a very repetitive process. Although this was quite repetitive, it made us observe every step of our experiment to make sure it was the most accurate we could make it.
In addition, one thing that could have made our experiment more accurate was taking our time with each step. I think the reason we had so many attempts was because we sometimes were so anxious and excited about testing the vial, we would remove too much weight, add too much, etc. These were key elements in having a successful experiment. Although we rushed our experiment as it became more exciting and interesting, we enjoyed each step of the process.
Conclusion:
The vial lab was a fun and interesting way to introduce the density formula. This lab was not very obvious; therefore it took all the groups time to create a valid hypothesis and experiment. My partner and I struggled in the beginning of the lab because we were both unsure at how to approach the lab. However, as we looked at our materials and information, we were able to unfold the key points that were essential to a successful experiment. Even given the density formula, it was still not an easy task. Furthermore, this lab was very frustrating, as we became closer and closer to our final answer. Each step was so close, yet so far. We either needed to at more weight or subtract weight; it was not a simple job. In addition, we were also very nervous with each step because we were sometimes unsure of the result. Finally, this was an interesting and challenging experiment, however we learned to take our time and try to be as accurate as possible.
Tuesday, September 16, 2008
Lollipop Lab Report
Jennifer Wilson
Chemistry 201-2
Mr. Schoudel
Introduction:
The scientific method is a key process when solving a problem in science. Questions, hypotheses, experiments, observations, gathering and analyzing data, and drawing a conclusion are all important steps in completing the scientific method. Our class has discussed this method and decided to construct an experiment that would follow the steps we outlined in the scientific method. The purpose of the lollipop experiment was to try to discover how many licks it takes to reach the tootsie filling of a tootsie pop. Our hypothesis was from Mr. Owl’s tootsie commercial, which stated that it takes exactly three licks to reach the chocolate filling of a tootsie pop. We found that there were many different variables that contributed to our experiment, such as the size of tongue, pressure of tongue when licking the lollipop, how one lick’s a lollipop, etc. There are many variables as well as limitations and restrictions that one must compromise with when testing a scientific question. As a class we did have some restrictions, such as time limit, space, and equipment. It was essential that we compromise and come up with an experiment that fit into the limitations of space and resources.
Hypothesis:
Our hypothesis was from Mr. Owl's tootsie commercial, which stated that it takes exactly three licks to reach the chocolate filling of a tootsie pop.
Materials:
• One tootsie pop for each student (15 lollipops)
• Multiple Glasses/Cups of water
• Students from each class (15)
• Stop watch to record time
• Pencil or pencil to record the data and results
• Controlled environment
Methods:
• Remove lollipop wrapper
• Take a sip of water (not a large gulp, but around 1 tablespoon of water)
• Lick the lollipop on one side for the entire time it takes to reach the chocolate center
• Count how many licks you take in three minutes
• Every three minutes take a sip of water
• Repeat steps 2 & 3 until you reach the chocolate filling of the tootsie pop
Data/Results:
Average Licks: 267.7
Median: 256
Mode: 312
Average of Mean, Median, & Mode: 278
Jennifer’s Results
Total # of licks: 261
Total Time: 8:30 Minutes
Discussion/ Analysis:
Our hypothesis for the lollipop lab was that it would take three licks to reach the chocolate filling of a tootsie pop. This is a false statement and is rarely every true due to the number of variables that are put into account. We discovered that it takes almost ninety times more licks to reach the center rather than three simple licks. Our entire class decided on taking sips of water every three minutes to keep our mouths moist, therefore making our experiment as consistent and accurate as possible. As a class we also decided to lick only one side of the lollipop and when that specific side displayed the chocolate filling, we had reached the center. We had a large debate about whether or not this was the more accurate lick. Many students said to put the entire lollipop in our mouth, while others said to just lick one side and keep it consistent.
To make our experiment more accurate, we could have put the entire lollipop in our mouths, which would represent the licks it took around the entire lollipop. Furthermore, we only took sips of water every three minutes. Our original time was five minutes, but we soon discovered that our mouth gets very dry and it is important to take a sip of water more frequently, to have an accurate experiment. There are also many variables to consider, such as the pressure one hits the lollipop, the type of lick, etc. If half of the class licked the lollipop on one side and the other lick the entire thing, but still keep the time consistent, we might have arrived at different averages. The main procedure that we would need to improve on is the type of lick and the speed at which you lick the lollipop.
Conclusion:
The lollipop experiment was a great way to begin the lesson on the scientific method. We were instructed to create a hypothesis, test our hypothesis, provide observations, gather and analyze date, and draw a conclusion. Although our hypothesis was incorrect we were able to identify several variables that had an affect on our experiment. In addition, we learned to compromise with our limitations and restrictions. In many situations there are always limitations and it is essential to compromise to carry out a successful experiment. During our experiment we noticed that students were reaching the center of the lollipop faster than others, which shows the pressure at which some licked the lollipop and the speed at which they licked. In an experiment like this, is it extremely difficult to come up with a perfect tester (in our conditions), which is why there were many variables to consider. Although we did not have many resources for this experiment, we had a lot of fun learning and working the scientific method.
Chemistry 201-2
Mr. Schoudel
Introduction:
The scientific method is a key process when solving a problem in science. Questions, hypotheses, experiments, observations, gathering and analyzing data, and drawing a conclusion are all important steps in completing the scientific method. Our class has discussed this method and decided to construct an experiment that would follow the steps we outlined in the scientific method. The purpose of the lollipop experiment was to try to discover how many licks it takes to reach the tootsie filling of a tootsie pop. Our hypothesis was from Mr. Owl’s tootsie commercial, which stated that it takes exactly three licks to reach the chocolate filling of a tootsie pop. We found that there were many different variables that contributed to our experiment, such as the size of tongue, pressure of tongue when licking the lollipop, how one lick’s a lollipop, etc. There are many variables as well as limitations and restrictions that one must compromise with when testing a scientific question. As a class we did have some restrictions, such as time limit, space, and equipment. It was essential that we compromise and come up with an experiment that fit into the limitations of space and resources.
Hypothesis:
Our hypothesis was from Mr. Owl's tootsie commercial, which stated that it takes exactly three licks to reach the chocolate filling of a tootsie pop.
Materials:
• One tootsie pop for each student (15 lollipops)
• Multiple Glasses/Cups of water
• Students from each class (15)
• Stop watch to record time
• Pencil or pencil to record the data and results
• Controlled environment
Methods:
• Remove lollipop wrapper
• Take a sip of water (not a large gulp, but around 1 tablespoon of water)
• Lick the lollipop on one side for the entire time it takes to reach the chocolate center
• Count how many licks you take in three minutes
• Every three minutes take a sip of water
• Repeat steps 2 & 3 until you reach the chocolate filling of the tootsie pop
Data/Results:
Average Licks: 267.7
Median: 256
Mode: 312
Average of Mean, Median, & Mode: 278
Jennifer’s Results
Total # of licks: 261
Total Time: 8:30 Minutes
Discussion/ Analysis:
Our hypothesis for the lollipop lab was that it would take three licks to reach the chocolate filling of a tootsie pop. This is a false statement and is rarely every true due to the number of variables that are put into account. We discovered that it takes almost ninety times more licks to reach the center rather than three simple licks. Our entire class decided on taking sips of water every three minutes to keep our mouths moist, therefore making our experiment as consistent and accurate as possible. As a class we also decided to lick only one side of the lollipop and when that specific side displayed the chocolate filling, we had reached the center. We had a large debate about whether or not this was the more accurate lick. Many students said to put the entire lollipop in our mouth, while others said to just lick one side and keep it consistent.
To make our experiment more accurate, we could have put the entire lollipop in our mouths, which would represent the licks it took around the entire lollipop. Furthermore, we only took sips of water every three minutes. Our original time was five minutes, but we soon discovered that our mouth gets very dry and it is important to take a sip of water more frequently, to have an accurate experiment. There are also many variables to consider, such as the pressure one hits the lollipop, the type of lick, etc. If half of the class licked the lollipop on one side and the other lick the entire thing, but still keep the time consistent, we might have arrived at different averages. The main procedure that we would need to improve on is the type of lick and the speed at which you lick the lollipop.
Conclusion:
The lollipop experiment was a great way to begin the lesson on the scientific method. We were instructed to create a hypothesis, test our hypothesis, provide observations, gather and analyze date, and draw a conclusion. Although our hypothesis was incorrect we were able to identify several variables that had an affect on our experiment. In addition, we learned to compromise with our limitations and restrictions. In many situations there are always limitations and it is essential to compromise to carry out a successful experiment. During our experiment we noticed that students were reaching the center of the lollipop faster than others, which shows the pressure at which some licked the lollipop and the speed at which they licked. In an experiment like this, is it extremely difficult to come up with a perfect tester (in our conditions), which is why there were many variables to consider. Although we did not have many resources for this experiment, we had a lot of fun learning and working the scientific method.
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