where does particulate matter come from?
TRANSCRIPT
PM Lesson 1
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PARTICULATE MATTER - LESSON ONE
Where Does Particulate Matter Come From? LESSON SUMMARY This lesson provides an introduction to the sources and some of the basic characteristics of airborne particulate matter (PM). By testing different types of samples with an air monitor, students begin to conceptualize that PM is emitted from a variety of sources, both indoors and outdoors. Students also have the opportunity to explore how PM can form through spontaneous chemical reactions in the air.
CORE UNDERSTANDING/OBJECTIVES By the end of this lesson, students should be able to identify common sources and characteristics of PM. They should also be able to identify their own primary sources of exposure to PM, both indoors and out. For specific learning objectives and standards addressed, see pages 19 & 20.
MATERIALS/INCORPORATION OF TECHNOLOGY Dylos Air Quality Monitor PM Testing samples (see p. 2) Solutions of BCG, KNO2, H2SO4, and NH3 Petri dishes & pipettes
INDIAN EDUCATION FOR ALL At 12%, asthma levels in Native American communities are nearly double that of the national average. A number of Native American scientists currently study air quality and respiratory health. For example, Northern Arizona University has developed a program called Indoor Air Quality in Tribal Communities (http://bit.ly/1H3OybG) in which they seek to raise awareness of indoor air quality issues among tribes in order to assist individuals in improving their living environments and managing their health risks.
ENGAGE OPTION 1: Using a large piece of paper, create a “Know, Want to Know, Learned” (KWL) chart for particulate matter. Students should have at least some background knowledge from the CAHHP introduction presentation provided by either a member of the CAHHP team or yourself. To help get students thinking in terms of what they already know about sources of PM, you can project the images from the following link: http://bit.ly/1zGOgnD . Using these images (if desired) as a source of inspiration, complete the “Know” column first. Next ask students what questions they would like answered throughout their studies of PM. Record these answers in the “Want to Know” column. This may also help students start thinking about what they may want to do for their air quality project/experiment. Complete the “Learned” column at the end of the lesson or unit.
Grade Level: 9 – 12
Subject(s) Addressed: General Science, Chemistry Class Time: 2 Periods
Inquiry Category: Guided
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OPTION 2: Divide students into groups of 3 or 4 and provide a large sheet of paper to each. Have the groups create a basic concept map of what they know about PM. Again, the images of PM sources from the following link can be used to provide inspiration: http://bit.ly/1zGOgnD . Give students 5-‐10 minutes in their small groups. Then have them rotate around the room to look at the different maps that were created. Students should note if they see any ideas that may be misconceptions. A list of questions regarding PM can then be generated on the board. EXPLORE
For a good overview of particle air pollution, visit: air pollution, visit: http://1.usa.gov/1DOeqph
Prior to class starting, gather a variety of PM source samples to test with the Dylos DC1700. You should have some samples that create airborne PM, as well as some samples that do not create PM. Some suggestions include:
Samples that create airborne PM: • candle • burning match • anything that produces dust (banging old carpet, sweeping, fanning the
pages of an old book, stomping on the carpet, etc.) • microwave popcorn (if microwave is available) • hairspray • aerosol air fresheners and cleaners (such as Lysol)
Samples that don’t create airborne PM:
• pure gas such as methane, which has odor, but is not PM • propane • acetone • water vapor** • Dry ice • perfume/cologne • Windex (or similar) spray
Provide students with “LAB 1: Exploring Particulate Matter” (pages 6 and 7). Explain to students that you will be looking at a variety of samples to see if they create airborne PM. Familiarize students with the Dylos monitor and how to read measurements of the two particles sizes. (A Dylos instructional video is available at http://bit.ly/1KHmgrv while written directions can be found at http://bit.ly/1gjMbce .) Gather students around the Dylos and turn it on. Ask students to note the resting (baseline) PM readings on the instrument (Note: this should be conducted between each sample as prior samples may not have completely dissipated before testing the next sample). Keeping the samples the same distance from the Dylos, preferably a few feet away to protect the instrument from any moisture or spills, begin testing samples. Students should record both PM2.5 and PM10 levels.
**Please note that water droplets rising off of boiling water will increase particle count readings on the Dylos if very close to the machine. However,
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unlike PM aerosols, the pure water droplets quickly dissipate as they evaporate.
EXPLAIN Using questions 1-‐4 from the Lab 1 student sheet as a framework, discuss the results with students. They should note that PM10 often comes from natural sources (dust, etc.), while PM2.5 is often associated with human activity (combustion sources, etc.). See Comprehension 1 (pages 13 & 14) for more detail on PM characteristics and sources. Try to engage students with leading questions, allowing them to form their own ideas. Contribute your expertise where it will allow their observations to grow.
ELABORATE At this point, students should be familiar with PM and some of its sources. They can now explore how PM can form from chemical reactions in the air. In LAB 2: “How do Secondary Particles Form?”, students observe the formation of nitric oxide, a product of fossil fuel combustion and a common component of airborne PM.
Note: If you have 50-‐minute class periods, you will need to do this activity on a different day. If you run on a block schedule, you may be able to complete this lab in the same class period as Lab 1.
Note: this lab does require the mixing of a number of chemical solutions in advance for student use. For a complete list of materials and teacher procedures, see pages 10 and 11. For student instructions and lab sheet, see pages 8 and 9.
EVALUATE There are a number of opportunities to evaluate student understanding throughout this lesson. The “Engage” activities provide opportunity to assess students’ prior knowledge. The formal labs and discussions described in the “Explain” section provide opportunities to assess student learning during the lesson. Additionally, the class should revisit the KWL chart to fill in the “Learned” column. This may be a good focus activity for starting the next day’s class. Any number of homework assignments are also possible. For example, students can create a flyer for the community about PM and indoor sources/exposures. This provides an opportunity for students to do some extra research, which may also inspire a topic for their project. The EPA website is an excellent resource with information such as PM air quality standards as well as the health effects related to long-‐term, elevated PM exposure. Equally there are comprehension guiding questions on page 16. VOCABULARY Copies of blank student vocabulary banks (page 4) can be distributed for completion as either a classroom or homework assignment.
To learn more about EPA standards and PM, visit: http://www.epa.gov/pm/
Montana DEQ monitors air quality conditions in a number of areas around the state. To check the air quality in your area visit: http://svc.mt.gov/deq/todaysair/
Notes:
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Name:
What is Particulate Matter – Vocabulary
Define the terms below and provide an example of each.
particulate matter:
PM2.5:
PM10:
coarse particles:
fine particles:
aerosols:
primary particles:
secondary particles
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What is Particulate Matter – Vocabulary
Define the terms below and provide an example of each.
particulate matter: solid and liquid particles found in the air. Examples include dust, smoke, by-‐products of industry, pollen, etc.
PM2.5: particles that are 2.5 microns or less in diameter. Examples include car emissions, smoke, etc.
PM10: particles that are 10 microns or less in diameter. Examples include dust and pollen.
coarse particles: particles that are between 2.5 and 10 microns in diameter. Examples: dust and pollen
fine particles: particles that are 2.5 microns or below. Examples include car emissions, smoke, etc.
aerosols: mixtures of fine solid particles or liquid droplets found the air or other gases. Examples: haze, smoke, fog
primary particles: particles emitted directly from a source. Example: wood smoke
secondary particles: particles that form through chemical reactions in the air. Example: particles that form from car emissions
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LAB 1: Exploring Particulate Matter
In this activity, you will be exploring a variety of possible air pollution sources, including ones that generate particulate matter. Using the Dylos monitor, observe the particle numbers created as different substances are released in the air. Remember that there are two particle readings, PM2.5 and PM2.5-‐10 -‐ be sure to record both. Using the table below, record your observations.
Drawing Conclusions:
1. Which samples did not increase particle count? ___________________________________________________________________________________________________________________________________
2. Do these samples have anything in common?
___________________________________________________________________________________________________________________________________
___________________________________________________________________________________________________________________________________
3. Using the table below, fill in which samples increased PM2.5 particle counts and which increased PM2.5-‐10 particle counts.
“Resting” PM Levels PM2.5 PM2.5-‐10
Sample/Substance PM2.5 Particle Count PM2.5-‐10 Particle Count
PM2.5 Particle Count PM2.5-‐10 Particle Count
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4. Looking at your lists above, what observations can you make about the characteristics of PM2.5 vs. PM2.5-‐10 particles?
_____________________________________________________________________________________________________________________________
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5. Which of the samples would be found indoors, outdoors, or both?
6. What other possible sources of particulate matter can you think of?
7. Now that you are more aware of some of the sources of particulate matter, identify the sources of PM within your own home. ________________________________________________________________________________________________________________________________
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8. What other indoor environments do you frequently find yourself in and what sources of PM might exist in these environments?
_________________________________________________________________________________________________________________________________
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9. Indoor air quality is a rapidly growing branch of scientific research. Why do you think this is? _________________________________________________________________________________________________________________________________
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10. As a class, take a 24-‐hour Dylos sample in your classroom. Once the data has been collected, again as a class,
download the data to a computer. Copy the data to a thumb drive and use the conversion Excel spreadsheet to
convert the data from number of particles to microgram/cubic meter, and to generate a graph. Print graph and
attach it here. What trends do you see over the 24-‐hour period?
________________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________________
What do you think may have caused these trends? ______________________________________________________________________
_________________________________________________________________________________________________________________________________
Indoors Outdoors Both
Indoor Outdoor
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LAB 2: How do Secondary Particles Form? Student Lab Sheet
In this lab you will be exploring how emissions can affect air quality by simulating chemical reactions that occur in the atmosphere. You will be synthesizing nitric oxide (NO) gas, a by-‐product of fossil fuel combustion. Nitric oxide, though a gas, can contribute to particle pollution, particularly in the winter months. In this lab, you will explore how and why NO forms and the potential impact(s) that occur from this reaction. You will be using a lidded petri dish as a contained environmental chamber.
Complete the following steps:
1. Place a clean, dry petri dish onto the circular grid of the labtop. 2. Using a pipette, put one drop of distilled water into the petri dish in the positions shown in the diagram. Then
drop a single drop of bromocresol green (BCG ) solution into each drop of distilled water. (See diagram on next page for a visual of this.) BCG is an indicator for acids and bases; any color changes indicate chemical changes in the petri dish. Observing these changes will help you understand what is produced in the following chemical reactions.
3. Now it’s time to create one of the by-‐products formed from the burning of fossils fuels: • Use a pipette to dispense 10 drops of 0.5 M KNO2 (potassium nitrate) into the center of the dish. • Get the lid of the petri dish ready (Note: you’ll want to cap the petri dish right away after the next step). • Use a clean pipette to measure and add 20 drops of H2SO4 (sulfuric acid) to the KNO2 in your dish. Cap the
petri dish immediately. • Watch carefully and record your observations:
__________________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________________
• Though the fluids never touched, the acidity changed. How is this possible? (Hint: consider the phases of matter) __________________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________________
• What gas is in your chamber at the moment (use the introduction paragraph to answer this)? _______________
4. You will now simulate another reaction: • Lift the lid slightly at an angle. Using a clean pipette, add a few of drops of 2 M ammonia (NH3) in four or
five places around the petri dish and replace the lid. • Carefully slide the petri dish off the grid and onto an all-‐black background. Watch carefully for a moment
and record your observations. ___________________________________________________________________________________________________________________________
___________________________________________________________________________________________________________________________
___________________________________________________________________________________________________________________________
• You can now test the substance in your petri dish by releasing it near the Dylos. To do this, set the dish one inch behind the machine. Record the particle levels before you open the lid, then open it and record the levels after. (Note: you will want to do this all relatively quickly for best results)
Before: PM2.5-‐ PM2.5-‐10-‐ After: PM2.5-‐ PM2.5-‐10-‐
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5. Did each particle count change after opening the lid? Using what you know about particulate matter formation, explain why or why not. ____________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________
6. In research studies done on seasonal levels of particle pollution, it has been found that secondary particles have
much higher concentrations in the summer months. Consider factors that affect the rates of chemical reactions. Why do you think there are more secondary particles in the summer months? Be sure to explain your answer. ____________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________
7. Finish the experiment by rinsing your petri dish in a lab sink, washing it with soap and water, and dabbing dry
with a cotton cloth (to avoid scratching).
Distilled H2O w/BCG
1 ml of 0.5 M KNO2
2 ml of 2 M H2SO4 added to the 0.5 M KNO2
A few drops of 2 M NH3
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LAB 2: Formation of Secondary Particles -‐ Teacher Resources
Small scale chemistry (SSC) involves conducting chemical experiments using smaller pieces of equipment and much reduced amounts of chemicals that are usually used in chemistry classes. SSC strives to get the most amount of information, in the simplest way, at the lowest cost, with the least amount of waste, and in the safest manner.
There are some tremendous advantages to working with small amounts of matter:
• SAFER: SSC uses fewer quantities of chemicals and durable containers whereas traditional teaching uses sharp glassware as well as large quantities of chemicals. Three most common injuries are cuts from broken glassware, burns from Bunsen burners, and chemical burns from concentrated acid spills.
• ENVIRONMENTALLY FRIENDLY: the disposal of wastes is cut to an absolute minimum. • ECONOMICAL: experiments can be conducted in a regular classroom; you don’t need a chemistry lab.
In SSC, the laboratory is an 8 ½ " x 11" laminated sheet called a labtop. The labtop contains a grid, white space and black space. It allows chemistry to be carried out in virtually any location and environment.
• HANDS-‐ON: because of the type of equipment and the smaller amounts of chemicals, each student can easily conduct his/her own experiments.
Chemical Recipes
You will need to make up four solutions in order to conduct this lab experiment with your class. You’ll need to use a measuring pipet (found in chemistry labs) to draw the solutions from their containers. Never use your mouth to draw the solutions. Either use an automatic pipet or a rubber bulb pipet aid.
For your own safety, please follow the instructions as written and wear a lab coat, safety glasses, and hand protection to prepare these solutions.
0.5 M potassium nitrite (KNO2)
Weigh out 1 gram of KNO2 and mix it with 25 ml of water until dissolved.
2 M sulfuric acid (H2SO4)
Take 5.6 ml of concentrated H2SO4 and add it slowly to 44.4 ml of water and stir frequently.
Note: It is important to add the acid to the water. If you add water to the acid, the solution could cause a violent reaction.
2 M ammonia (NH3)
Take 3.4 ml concentrated NH3 and add it slowly to 21.6 ml of water and stir frequently.
0.03% bromocresol green
Weigh out 0.03 grams of bromocresol green and mix with 100 ml of water until dissolved. If you have an accurate balance you can weigh out half the amount and mix with 50 ml of water.
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The amounts are designed to make 25 ml each of potassium nitrate and ammonia, 45 ml of sulfuric acid, and 100 ml of the bromocresol green. The first three solutions can be made up well in advance, but the bromocresol green solution should be made within a couple days of when you intend to run the experiment. This will be sufficient for approximately 24 students working in pairs. Remember to always add an acid or base to water slowly with mixing to prevent heat buildup and potential splashing.
Material List
• Student experiment sheet • Printed, laminated labtop (pg. 11) • Chemicals (Teachers pour small amounts of each needed chemical into plastic cups. Teachers – or students – draw chemical from cup into correspondingly labeled pipet -‐ also called a microburet.
• Each pair of student gets their own set of chemicals: o 0.5 M KNO2 potassium nitrite o 2 M H2SO4 sulfuric acid o 2 M NH3 ammonia o BCG bromocresol green
• Small Scale Chemistry Equipment (1 for each pair of students): o plastic Petri dishes o labtops
• Clean up
o detergent for washing Petri dishes o cotton cloth for drying (to avoid scratching)
Notes:
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Labtop
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LAB 2: How do Secondary Particles Form? Teacher Key
In this lab you will be exploring how emissions can affect air quality by simulating chemical reactions that occur in the atmosphere. You will be synthesizing nitric oxide (NO) gas, a by-‐product of fossil fuel combustion. Nitric oxide, though a gas, can contribute to particle pollution, particularly in the winter months. In this lab, you will explore how and why NO forms and the potential impact(s) that occur from this reaction. You will be using a lidded petri dish as a contained environmental chamber.
Complete the following steps:
1. Place a clean, dry petri dish onto the circular grid of the labtop. 2. Using a pipette, put one drop of distilled water into the petri dish in the positions shown in the diagram. Then
drop a single drop of bromocresol green (BCG ) solution into each drop of distilled water. (See diagram on next page for a visual of this.) BCG is an indicator for acids and bases; any color changes indicate chemical changes in the petri dish. Observing these changes will help you understand what is produced in the following chemical reactions.
3. Now it’s time to create one of the by-‐products formed from the burning of fossils fuels: • Use a pipette to dispense 8 drops of 0.5 M KNO2 (potassium nitrate) into the center of the dish. • Get the lid of the petri dish ready (Note: you’ll want to cap the petri dish right away after the next step). • Use a clean pipette to measure and add 16 drops of H2SO4 (sulfuric acid) to the KNO2 in your dish. Cap the
petri dish immediately. • Watch carefully and record your observations:
Students should observe color changes in the drops of distilled water & BCG
Though the fluids never touched, the acidity changed. How is this possible? (Hint: consider the phases of matter) There must be a phase change in one or more the chemicals which turn to gas and circulate around the petri dish, changing the acidity of the environment.
• What gas is in your chamber at the moment (use the introduction paragraph to answer this)? Nitric Oxide
4. You will now simulate another reaction:
• Lift the lid slightly at an angle. Using a clean pipette, add a couple of drops of 2 M ammonia (NH3) in four or five places around the petri dish and replace the lid.
• Carefully slide the petri dish off the grid and onto an all black background. Watch carefully and record your observations.
Students should see particles forming in the petri dish. Wispy white vapors will appear.
• You can now test the substance in your petri dish by releasing it near the Dylos. To do this, set the dish 6 inches behind the machine. Be sure to record the particle levels before you open the lid to the petri dish, as well as after. Before: PM2.5-‐ Varies PM2.5-‐10-‐ Varies After: PM2.5-‐ Varies PM2.5-‐10-‐ Varies
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5. Did each particle count change after opening the lid? Using what you know about particulate matter formation, explain why or why not. Students should see the particle count go up, and should draw the conclusion that the spontaneous chemical reaction in the petri dish created secondary particles.
6. In research studies done on seasonal levels of particle pollution, it has been found that secondary particles have
much higher concentrations in the summer months. Consider factors that effect the rates of chemical reactions. Why do you think there are more secondary particles in the summer months? Be sure to explain your answer. When temperature increases, so does the rate of chemical reactions. Therefore, in the summer months when air temperatures are higher, the chemical reactions that create secondary particles are happening at an increased rate.
7. Finish the experiment by rinsing your petri dish in a lab sink, washing it with soap and water, and dabbing dry with a cotton cloth (to avoid scratching).
Distilled H2O w/BCG
1 ml of 0.5 M KNO2
2 ml of 2 M H2SO4 added to the 0.5 M KNO2
A few drops of 2 M NH3
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COMPREHENSION 1
What are the Sources of Particulate Matter?
WHAT IS PARTICULATE MATTER? The term "particulate matter" (PM) includes both solid particles and liquid droplets found in air. Many manmade and natural sources emit PM, both indoors and out, including wildland fires, fossil fuel emissions, road dust, wood stove and fireplace emissions, volcanoes, cigarette smoke, and cooking. All forms of particulate matter belong to one of two groups: primary (emitted directly from a source) or secondary (formed through chemical reactions in the air). Secondary particles make up most of the fine particle pollution in the country. Particles can be further categorized based on their chemical composition. For instance, the composition of diesel PM would contain more elemental carbons while PM from wood smoke would have more organic carbons.
Below are the common components of PM and some of their sources:
• sulfates, often associated with emissions from industry • nitrates, from fossil fuel emission and agriculture • organic compounds, from all types of combustion, industry, agriculture • water, vapor from the water cycle • trace elements (including metals), some are naturally occurring from crustal sources (aka from the Earth’s crust), others from industry and burning of fossil fuels
It is important to note that the possible human health effects vary greatly depending on the source and composition of particles. For example, particles formed from car and industry emissions are known to be much more hazardous than dust particles. Particulate matter is also categorized by size. PM10 particles include those with a diameter of 10 microns and less. A micron is one millionth of a meter (1/1,000,000 m). Many of these can be seen with the naked eye, such as dust and pollen. PM2.5 is 2.5 microns or less in diameter. You may equally hear people discuss “coarse” vs. “fine” particles. Fine particles are 2.5 microns or less in diameter. Coarse particles are those that measure between 2.5 microns and 10 microns. The distinction between PM10 and coarse particles is subtle but significant; PM10 includes all particles between 0.1 and 10 microns, while coarse particles only account for those between 2.5 and 10 microns. When looking at a PM10 reading, you are seeing the total number of coarse and fine particles. By subtracting the corresponding PM2.5 reading, you get your “coarse particle fraction”.
There are many informational There are many informational resources available for particulate matter. Start by exploring the EPAs website: exploring the EPAs website:
http://1.usa.gov/1DOeqph
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Below is a chart that shows common particulate matter pollutants and their respective size ranges:
WHAT ARE THE HEALTH EFFECTS OF PARTICULATE MATTER? There are a number of known health concerns associated with particulate matter, though it is still not fully understood and it is the focus of many scientific studies. As mention above, the possible health effects depend on the source and composition of the PM. Wood smoke is known to increase susceptibility to respiratory infections, while fossil fuel emissions are associated with cardiovascular problems, such as non-‐fatal heart attacks and cardiac arrhythmia (irregular heartbeat), and lung cancer. Many scientists focus on PM2.5 as it is so small that it can bypass the body’s natural defenses – nose hairs and cilia – and make it down through the larynx into the respiratory system, and penetrate deep into the lungs. For individuals with heart or lung disease it can even cause premature death. Other individuals who are particularly at risk to particle matter exposure include sensitive populations such as older adults, people with compromised immune systems, and children. It is important to consider that length of exposure to PM is a critical factor in what health effects are seen. Short-‐term exposure may result in respiratory difficulty, while long-‐term can cause more severe health issues such as cardiovascular disease and premature death.
Regulation of Particulate Matter With the number of health concerns associated with particulate matter, as well as its broader environmental effects, the Environmental Protection Agency (EPA) enforces strict regulations on emissions as a part of the Clean Air Act. Levels are based on outdoor 24 hour averages measured in micrometers per m3 (µ/m3). Daily levels for PM2.5 is 35 µ/m3 and is not to exceed an overall annual average of 15µ/m3. For PM10 it is 150 µ/m3 with an annual average level at or below 50. Communities that exceed these levels are considered “non-‐attainment” areas and are required to create state implementation plans addressing how to improve pollutant levels.
Notes:
Read the EPAs “Fast Facts” for more interesting facts on PM: http://1.usa.gov/1KpvHJi
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PM LESSON 1: Comprehension Guiding Questions
1. What is the difference between PM2.5 and PM10?
2. Why are scientists so concerned about PM2.5?
3. What is the distinction between coarse particles and PM10?
4. The EPA (Environmental Protection Agency) has set acceptable average levels of particulate matter pollution in a 24-‐hour period. What is the acceptable average 24-‐hour ambient (outdoor) level for PM2.5? For PM10?
5. What is the difference between primary and secondary particles? Provide at least one example of each.
6. What type of particles (primary or secondary) make up the majority of particle pollution in the US?
7. Match the PM2.5 species with the sources in the second column. Note, more than one source may match a species, and sources can match multiple species: __________ a) nitrate __________ b) carbon __________ c) crustal __________ d) sulfate
1. dust 2. car exhaust 3. agriculture 4. ash 5. smoke/fire 6. industry
8. What are some of the health effects of particulate matter exposure and with which source are each associated?
9. Select your state on the map at the following link. There you will be able to explore the primary sources of particulate matter pollution by county in your state. Select your own county first. Then explore at least 5 other counties in your state. Summarize and explain your findings. http://1.usa.gov/16AGO39
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PM Lesson 1: Guiding Questions -‐ Teacher Key
1. What is the difference between PM2.5 and PM10? PM10, is 10 microns or less in diameter, while PM2.5, measures 2.5 microns or less in diameter.
2. Why are scientists so concerned about PM2.5? At such a small size, PM2.5 can bypass the body’s natural defenses and can embed themselves deep in the lungs, causing a number of health issues.
3. What is the distinction between coarse particles and PM10? Coarse particles do not include particles below 2.5 microns, while PM10 does.
4. The EPA (Environmental Protection Agency) has set acceptable average levels of particulate matter pollution in a 24-‐hour period. What is the acceptable average 24-‐hour ambient (outdoor) level for PM2.5? For PM10? PM2.5: 35 micrograms/m3 or less PM10: 150 micrograms/m3 less
5. What is the difference between primary and secondary particles? Provide at least one example of each. Primary particles are emitted directly from a source, such as wood smoke or dust from unpaved roads. Secondary particles form through complex chemical reactions. Some example sources of these chemicals are emissions from cars or factories. A secondary particle includes ammonium nitrate or ammonium sulfate.
6. What type of particles (primary or secondary) make up the majority of particle pollution in the US? Secondary
7. Match the PM2.5 sources in the second column to the sources in the first column. Note, sources can match more than one species: __________ a) nitrate __________ b) carbon __________ c) crustal __________ d) sulfate
7. dust 8. car exhaust 9. agriculture 10. ash 11. smoke/fire 12. industry
8. What are some of the health effects particulate matter exposure and with which source are each associated?
Asthma (woodsmoke), non-‐fatal heart attacks and lung cancer (fossil fuel emissions), decreased lung function.
9. Select your state on the map at the following link. There you will be able to explore the primary sources of particulate matter pollution by county in your state. Select your own county first. Then explore at least 5 other counties in your state. Summarize and explain your findings. http://1.usa.gov/16AGO39 Students should be able to identify the primary sources of PM in their region as well as explain some of the differences across the state. For example, smoke is the primary source of PM pollution in Missoula County. In many of the central Montana counties, a primary source is nitrates which reflects the amount of agriculture in those areas. Equally, some counties have dust as a major contributor, which is explained by the dry, open landscape.
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Particulate Matter Lesson 1: Specific Learning Objectives and Standards Specific Learning Objectives Upon completion of this lesson, students will be able to:
• define particulate matter. • identify common sources of particulate matter. • differentiate between PM2.5 and PM10, as well as primary and secondary particles. • identify their primary exposures to particulate matter. • observe basic chemical reaction simulating secondary particle formation and provide basic explanation. • identify temperature as a factor that effects chemical reactions and explain what that effect is.
NEXT GENERATION SCIENCE STANDARDS Students who demonstrate understanding can:
HS-‐PS1-‐2 Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.
HS-‐PS1-‐6 Apply scientific principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on the rate at which a reaction occurs.
MONTANA STATE SCIENCE STANDARDS A proficient student will (upon graduation):
Science Content Standard 1: Students, through the inquiry process, demonstrate the ability to design, conduct, evaluate, and communicate the results and form reasonable conclusions of scientific investigations.
1.1 generate a question, identify dependent and independent variables, formulate testable, multiple hypotheses, plan an investigation, predict its outcome, safely conduct the scientific investigations, and collect and analyze data. 1.4 analyze observations and explain with scientific understanding to develop a plausible model (e.g., atom, expanding universe).
Science Content Standard 2: Students, through the inquiry process, demonstrate knowledge of properties, forms, changes and interactions of physical and chemical systems.
2.3 describe the major features associated with chemical reactions, including (a) giving examples of reactions important to industry and living organisms, (b) energy changes associated with chemical changes, (c) classes of chemical reactions, (d) rates of reactions and (e) the role of catalysts.
ALASKA STATE SCIENCE STANDARDS SA1: Students develop an understanding of the processes of science used to investigate problems, design, and conduct repeatable scientific investigations, and defend scientific arguments.
[10] SA1.1 The student demonstrates an understanding of the processes of science by asking questions, predicting, observing, describing, measuring, classifying, making generalizations, analyzing data, developing models, inferring, and communicating.
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SC3: Students develop an understanding that all organisms are linked to each other and their physical environments through the transfer and transformation of matter and energy.
[11] SC3.2 The student demonstrates an understanding that all organisms are linked to each other and their physical environments through the transfer and transformation of matter and energy by analyzing the potential impacts of changes (e.g., climate change, habitat loss/gain, cataclysms, human activities) within an ecosystem.
SE3: Students develop an understanding of how scientific discoveries and technological innovations affect and are affected by our lives and cultures.
[10] SE3.1/[11] SE3.1 The student demonstrates an understanding of how scientific discoveries and technological innovations affect our lives and society by researching a current problem, identifying possible solutions, and evaluating the impact of each solution.
IDAHO STATE STANDARDS Chemistry:
Goal 1.3: Understand Constancy, Change, and Measurement 11-‐12.C.1.3.1 Identify, compare and contrast physical and chemical properties and changes and appropriate computations.
Goal 1.8: Understand Technical Communication 11-‐12.C.1.8.2 Communicate scientific investigations and information clearly.
Goal 2.5: Understand Chemical Reactions 11-‐12.C.2.5.3 Describe the factors that influence the rates of chemical reactions.
Goal 5.1: Understand Common Environmental Quality Issues, Both Natural and Human Induced
11-‐12.C.5.1.1 Demonstrate the ability to work safely and effectively in a chemistry laboratory. Goal 5.3: Understand the Importance of Natural Resources and the Need to Manage and Conserve Them
11-‐12.C.5.3.1 Evaluate the role of chemistry in energy and environmental issues.