Air Quality Lab
Pre-Lab Questions
- Create a chart showing the six air pollutants, causes, and concerns from the information in the pre-lab.
chart | |
File Size: | 95 kb |
File Type: | chart |
2. Why is ground level ozone highest in the summer and almost nonexistent in the winter? How might this affect our results as we test the air during this part of the year?
Ground level ozone is created from a mix of chemicals, heat, and sunlight. In the summer, heat and sunlight are present, while in the winter, there's no heat and not a lot of sunlight.
3. Many third world countries still use leaded gasoline (since they have older cars or since they have not forced changes). What concerns may the governments of these countries need to deal with?
Plants and animals are going to have lead in them. Lead causes people to have brain damage and heart disease. Governments are concerned with their communities health, in case there's a spill or filling up your car.
4. Use the internet to find what parts of North Carolina are not in compliance with the Standards of the Clean Air Act. You may give either general areas or specific counties.
The mid-section of North Carolina, including Greensboro and Charlotte, exceeds the standards, while the rest of North Carolina does not reach the standards.
Ground level ozone is created from a mix of chemicals, heat, and sunlight. In the summer, heat and sunlight are present, while in the winter, there's no heat and not a lot of sunlight.
3. Many third world countries still use leaded gasoline (since they have older cars or since they have not forced changes). What concerns may the governments of these countries need to deal with?
Plants and animals are going to have lead in them. Lead causes people to have brain damage and heart disease. Governments are concerned with their communities health, in case there's a spill or filling up your car.
4. Use the internet to find what parts of North Carolina are not in compliance with the Standards of the Clean Air Act. You may give either general areas or specific counties.
The mid-section of North Carolina, including Greensboro and Charlotte, exceeds the standards, while the rest of North Carolina does not reach the standards.
Hypothesis
There will be a lot of particulate matter and a small amount of ozone in the shop behind the theatre. There will be a small amount of particulate matter outside and a medium amount of ozone.
Variables
Experimental Set-up
Variables
- Independent variable: location of the particulate matter and ozone measurements
- Dependent variable: measurement of particulate matter and ozone
- Controlled variables: index card, petroleum jelly, paper, string, ozone solution
Experimental Set-up
- Control Group: paper and index card, undipped and without petroleum jelly
- Experimental Group(s): 1. paper dipped in ozone solution, and index card with petroleum jelly smeared on it hung in the shop behind the theatre, 2. paper dipped in ozone solution, and index card with petroleum jelly smeared on it hung outside in the parking lot on a tree
Problem
How can the ozone level and particulate matter consistency be found inside and outside?
Materials
- Potassium Iodide
- Corn starch
- Beakers
- Spatulas
- Large Graduated Cylinder
- Test Tube Rack
- Filter Paper
- Microscope slides
- Petroleum Jelly
- Q-tips
- Microscopes
Procedure
Preparation
1. Half the class should work on preparing the ozone monitoring test strips by placing 100ml of water in a 250 ml beaker, and adding 5g of cornstarch. Then heat and stir the mixture until it gels (when the mixture becomes thick and clear). Remove the solution from heat, add 1 g of potassium iodide, stir well, and allow to cool. After the solution has cooled, lay a piece of filter paper on a petri and brush the paste onto the filter paper. Turn the filter paper and brush the paste on the other side. Hang up and allow the filter paper to dry. Cut the papers into 1 inch-wide strips. Store the strips in a plastic bag out of sunlight.
2. The other half of the class will prepare Particulate matter collectors by smearing a thin layer of petroleum jelly onto a microscope slides. Try to make the layer as even as possible. Use a q-tip to lightly smear the specimen side of each slide. You will need to prepare 2 slides per group and place them in a slide container to avoid smearing the petroleum jelly on anyone.
Data Collection
3. Each group will place one labeled slide on the exterior of the school. Some groups should choose areas that would receive few particulates, others should choose locations that produce more particulates. (Keep in mind sources of particulate matter)
4. One member from each group should take the second slide and place it in a location inside the school.
5. You should then place your ozone monitoring strip outside for 8 hrs. Before placing the strip outside, dip the strip in distilled water, then attach the strip out of sunlight. When placing your strip find the relative humidity for that day.
6. The next day, each group should collect their slide and ozone monitoring strip.
7. Dunk each strip into distilled water. Use the chart at the right to determine the Schoenbein Number of your strip.
Christian Friedrich Schoenbein discovered ozone in 1839 during his tenure as a professor at the University of Basel, Switzerland. He used the reactivity of ozone to measure its presence and demonstrate that it is a naturally occurring component of the atmosphere. He developed a way to measure ozone in the troposphere using a mixture of starch, potassium iodide, and water spread on filter paper. The paper, called Schoenbein paper, changes color when ozone is present. Ozone causes iodide to oxidize into iodine ().
This test is based on the oxidation capability of ozone. Ozone in the air will oxidize the potassium iodide on the test paper to produce iodine. The iodine reacts with starch, staining the paper a shade of purple. The intensity of the purple color depends on the amount of ozone present in the air. The darker the color, the more ozone is present.
The reactions involved are:
2KI + O3 + H2O --> 2KOH + O2 + I2
I2 + starch --> blue color
8. Use the relative humidity and the Schoenbein number to calculate the concentration of ground level ozone using the chart below.
9. Look at your particulate matter slide under the microscope. First decide the amount of particulates and then attempt to estimate the source of the PM. Your group will need to decide how you can classify what type of PM was collected.
10. Make sure you record all you lab information into your notebook.
1. Half the class should work on preparing the ozone monitoring test strips by placing 100ml of water in a 250 ml beaker, and adding 5g of cornstarch. Then heat and stir the mixture until it gels (when the mixture becomes thick and clear). Remove the solution from heat, add 1 g of potassium iodide, stir well, and allow to cool. After the solution has cooled, lay a piece of filter paper on a petri and brush the paste onto the filter paper. Turn the filter paper and brush the paste on the other side. Hang up and allow the filter paper to dry. Cut the papers into 1 inch-wide strips. Store the strips in a plastic bag out of sunlight.
2. The other half of the class will prepare Particulate matter collectors by smearing a thin layer of petroleum jelly onto a microscope slides. Try to make the layer as even as possible. Use a q-tip to lightly smear the specimen side of each slide. You will need to prepare 2 slides per group and place them in a slide container to avoid smearing the petroleum jelly on anyone.
Data Collection
3. Each group will place one labeled slide on the exterior of the school. Some groups should choose areas that would receive few particulates, others should choose locations that produce more particulates. (Keep in mind sources of particulate matter)
4. One member from each group should take the second slide and place it in a location inside the school.
5. You should then place your ozone monitoring strip outside for 8 hrs. Before placing the strip outside, dip the strip in distilled water, then attach the strip out of sunlight. When placing your strip find the relative humidity for that day.
6. The next day, each group should collect their slide and ozone monitoring strip.
7. Dunk each strip into distilled water. Use the chart at the right to determine the Schoenbein Number of your strip.
Christian Friedrich Schoenbein discovered ozone in 1839 during his tenure as a professor at the University of Basel, Switzerland. He used the reactivity of ozone to measure its presence and demonstrate that it is a naturally occurring component of the atmosphere. He developed a way to measure ozone in the troposphere using a mixture of starch, potassium iodide, and water spread on filter paper. The paper, called Schoenbein paper, changes color when ozone is present. Ozone causes iodide to oxidize into iodine ().
This test is based on the oxidation capability of ozone. Ozone in the air will oxidize the potassium iodide on the test paper to produce iodine. The iodine reacts with starch, staining the paper a shade of purple. The intensity of the purple color depends on the amount of ozone present in the air. The darker the color, the more ozone is present.
The reactions involved are:
2KI + O3 + H2O --> 2KOH + O2 + I2
I2 + starch --> blue color
8. Use the relative humidity and the Schoenbein number to calculate the concentration of ground level ozone using the chart below.
9. Look at your particulate matter slide under the microscope. First decide the amount of particulates and then attempt to estimate the source of the PM. Your group will need to decide how you can classify what type of PM was collected.
10. Make sure you record all you lab information into your notebook.
Observations and Data
Observations
There was a lot of ozone in the shop behind the theatre, but no particulate matter. The ozone measurement is not available for outside, but there was light particulate matter measured.
Data Table
There was a lot of ozone in the shop behind the theatre, but no particulate matter. The ozone measurement is not available for outside, but there was light particulate matter measured.
Data Table
air_quality_data_2012.docx | |
File Size: | 14 kb |
File Type: | docx |
Analysis and Conclusion
1. The highest rating the EPA will allow for a community for ground level ozone is 80 ppb. Any community with over 80 ppb for an average over three years is in noncompliance with the Clean Air Act. Compare your number to this standard. Did Wake Forest meet the standard on this day? Using what you know about the formation of ozone, decide if you believe the measurement you made was an accurate measurement of the air quality and why.
Wake Forest did not meet the standard. It was in the lower 40s that day. The group's outside ozone measurement was not completed because the rain washed it away over the weekend.
2. 13% of counties in the US are not meeting the Ozone requirements of the Clean Air Act. Use the chart below and information from class to explain the reason for the location of the counties in Non-attainment.
The reason those counties do not meet the standard is because of the geography in the surrounding area. Most counties are on the coast and the fact might be because of the winds coming in.
3. Particulate matter has recently been added to the requirements of the Clean Air Act. Theorize reasons that it was not part of the act until the 1990’s.
Particulate matter was not a concern then because it was virtually absent. Nobody thought about particulate matter. It existed, just was not worried about.
4. Compare and contrast the different PM samples – did they meet your expectations? Why or why not?
No, the PM samples were not what was expected. The one placed in the shop behind the theatre did not have any particulate matter, while the one placed outside had light. It was thought that the one inside would be covered in PM.
5. Explain why air quality monitoring is important for the health of the economy.
Because the economic system relies on the health of the country's citizens, air quality monitoring is needed so people can stay healthy. Bad air quality can cause sicknesses like asthma, coughing, and sometimes can cause premature death. The country needs to pay attention to air quality because it can cause these things, and for the sake of the economy.
Wake Forest did not meet the standard. It was in the lower 40s that day. The group's outside ozone measurement was not completed because the rain washed it away over the weekend.
2. 13% of counties in the US are not meeting the Ozone requirements of the Clean Air Act. Use the chart below and information from class to explain the reason for the location of the counties in Non-attainment.
The reason those counties do not meet the standard is because of the geography in the surrounding area. Most counties are on the coast and the fact might be because of the winds coming in.
3. Particulate matter has recently been added to the requirements of the Clean Air Act. Theorize reasons that it was not part of the act until the 1990’s.
Particulate matter was not a concern then because it was virtually absent. Nobody thought about particulate matter. It existed, just was not worried about.
4. Compare and contrast the different PM samples – did they meet your expectations? Why or why not?
No, the PM samples were not what was expected. The one placed in the shop behind the theatre did not have any particulate matter, while the one placed outside had light. It was thought that the one inside would be covered in PM.
5. Explain why air quality monitoring is important for the health of the economy.
Because the economic system relies on the health of the country's citizens, air quality monitoring is needed so people can stay healthy. Bad air quality can cause sicknesses like asthma, coughing, and sometimes can cause premature death. The country needs to pay attention to air quality because it can cause these things, and for the sake of the economy.