1. What is Indoor Air Pollution?
(one class period)
Learning objectives
Students will be able to identify the main indoor air pollutants, their sources and explain the general health effects of indoor air pollution
Materials and teacher-developed resources
-
Paper, pencils, software (ActivInspire / Promethean)
Learning activities
For the first part of the lesson, students will read the article “On the History of Indoor Air Quality and Health”. Then, the teacher will split the students in groups of three or four and conduct a class discussion about the topics mentioned above. Ask students to describe the differences in air pollution at home and in classroom (if any). For homework, ask students to write a paper about the steps they can take to control and reduce indoor air pollution.
2. Modeling the concentration of Carbon Dioxide concentration in a classroom
(two class periods)
Learning objectives
Students will answer the following question: “How much a classroom must be ventilated in order to keep the concentration of carbon dioxide at a low level”?
Materials and teacher-developed resources
-
Paper, pencils, software (ActivInspire / Promethean
)
-
Carbon Dioxide monitors
Learning activities
Using the carbon dioxide monitors, students will observe and record the concentration of carbon dioxide in their classroom over a period of three days. They will use the collected data to calculate the mass balance of gases entering and exiting the classroom to find the equation for the optimal air exchange rate (for the given volume of the classroom) that keeps the carbon dioxide concentration at a low level.
The mass balance for removal of any indoor contaminant can be expressed by the following equation:
ΔM / Δt = Q x C
0
- Q x C
f
+ G – L
where
ΔM is the change of mass of contaminant inside the classroom during the time interval Δt (measured in mg/min)
Q represents the fresh airflow rate into the classroom that is equal to the exhaust airflow rate (measured in m
3
/min)
C
0
is the outdoor (initial) concentration of contaminant entering the classroom (measured in mg/m
3
)
C
f
is the final concentration of contaminant exiting the classroom (measured in mg/m
3
)
G represents the generation (emission) rate of contaminant in the classroom (measured in mg/min)
L represents the loss rate (filtration or deposition) of a contaminant in the classroom (measured in mg/min)
Assuming that airflow (Q) and generation (G, L) rates are constant and the room is at steady state (ΔM / Δt is 0), the equation becomes
L – G = Q (C
0
- C
f
)
Solving for the flow rate, in the differential format, the equation becomes:
Q = (L – G) / (C
0
- C
f
)
Because flow rate represents the ratio between volume and time (Q = V / t), if we know the volume of the classroom (m
3
), we can find the air exchange rate (Q/V)
Q/V = 1/t= (L-G) / V(C
0
- C
f
)
in min
-1
3. Organic vs. Inorganic Compounds Lesson plan
(one class period)
Learning objectives
Students will be able to distinguish between inorganic and organic compounds and describe the main differences between the two classes of compounds.
Materials and teacher-developed resources
-
Paper, pencils, software (power point presentation)
-
Few 100 ml jars containing sugar, table salt, ethylic alcohol, coffee, water, a piece of metal, wood, paper, a small dish containing copper sulphate
Learning activities
The teacher will explain that organic compounds can be found in living organisms and mainly contain carbon and hydrogen. These compounds are very complex and come in huge number. The inorganic compounds, with few exceptions, do not contain carbon and hydrogen, their molecules are less complicated and come in smaller number compared to organic compounds. The most organic compounds contain the C-H bonds under different types (simple, double, triple) and the teacher will give examples. With the teacher’s help, students will identify the most commonly used organic and inorganic compounds. Also, the teacher will point out that there are some organic compounds (carbon tetrachloride, urea) that do not contain carbon-hydrogen bonds and that there are some inorganic compounds (carbon oxides, carbides, carbonates) that contain carbon. Finally, the teacher will provide the students with a list of chemicals and ask students to identify the inorganic and organic compounds.
4. Organic Compounds Nomenclature Lesson plan
(one class period)
Learning objectives
Students will be able to name the simplest organic compounds according to IUPAC system.
Materials and teacher-developed resources
-
Paper, pencils, software (power point presentation)
Learning activities
The teacher will explain the rules that guide the naming of organic compounds and help students name the alkanes (saturated hydrocarbons with a single bond between carbon atoms), alkenes (unsaturated hydrocarbons with at least one double bond between carbon atoms) and hydrocarbons with side groups (groups that come off of the main carbon-carbon chain).
5. Aromatic Compounds Lesson plan
(two class periods)
Learning objectives
Students will be able to define, name and recognize monocyclic and polycyclic aromatic compounds
.
They will identify the aromatic compounds that are indoor air pollutants.
Materials and teacher-developed resources
-
Paper, pencils, software (power point presentation)
-
Two small bottles containing benzene and toluene
Learning activities
The teacher will introduce the characteristics of aromatic compounds and explain the basic structure of benzene, C
6
H
6
(the simplest aromatic compound), a very stable compound with a structure of a ring in which the electrons are equally shared by all six carbon atoms. Students will learn about the physical and chemical properties of aromatic compounds, naming and rules for numbering substituents on the benzene’s ring. Also, the teacher will introduce the formulas and structures of compounds with double benzene rings (naphthalene) and triple benzene rings (anthracene, phenanthrene
).
On the second class period, the students will discuss and identify the steps to reduce indoor exposure to the aromatic compounds.