At a glance
Pairs · launched in Unit 5 and due four classes later · three working periods · one Canadian location, its real air quality record, and one honest paragraph about what is putting it there
The situation
The gas laws describe a sample in a syringe. The atmosphere is the sample nobody can control, everybody shares, and every combustion reaction in this course has contributed to. This brief points the chemistry at it.
You are writing for somebody who lives in the place you choose — a council, a school community, a local paper. Two pages, and every number sourced.
What must be in it
1. The location, and why you chose it. Somewhere in Canada you have a reason to care about: where you live, where family is, somewhere a news story sent you.
2. The record, read properly. Use Environment Canada’s Air Quality Health Index for that location, over a period long enough to show a pattern — a season, ideally a year. Report:
- the usual reading, and the range;
- when it was worst, and what was happening then;
- which pollutant drove the index on the worst days.
State the period you looked at and where the data came from. A single day’s reading is an anecdote.
3. The chemistry underneath. For the pollutant that drove your worst days, what reaction produces it, and from what activity? Balanced equations where you can write them — combustion of hydrocarbons, sulfur dioxide from smelting, nitrogen oxides at high combustion temperatures, ground-level ozone formed by reactions in sunlight. Combustion and Gases and the Atmosphere are where the course has met these.
4. The cumulative part. One car is not the problem, and neither is one furnace. Explain, in your own words, why “each source is small” and “the total is serious” are both true — the arithmetic of that is the whole point of this brief.
5. One realistic measure, and who would have to act. Not “people should drive less”: something a named body could actually do, with what it would change.
The working periods
| Day | What it is for |
|---|---|
| 1 | Location chosen; the index data pulled and tabulated |
| 2 | The chemistry: reactions identified and balanced |
| 3 | Draft read by another pair, who challenge one unsourced claim each |
How this is assessed
| Quality | What it looks like |
|---|---|
| Data read honestly | A period, not a day; the range as well as the average |
| Sourced | Every number traceable, the index named as the source |
| Chemistry is correct | Equations balanced; the right reaction for the right pollutant |
| Cumulative effects understood | Explains why small sources add to a real problem |
| Measure is realistic | Specific, addressed to somebody who could do it |
| Written for the reader | Two pages a non-chemist finishes and understands |
Reflect
A Chemistry Journal entry: what did you expect the record to show, and what did it actually show? And which of this semester’s reactions turned out to be happening, at scale, over the place you chose?
Curriculum connection
F1.1
analyse the effects on air quality of some technologies and human activities (e.g., smelting; driving gas-powered vehicles), including their own activities, and propose actions to reduce their personal carbon footprint [AI, C]
Link to original
F1.2
assess air quality conditions for a given Canadian location, using Environment Canada’s Air Quality Health Index, and report on some Canadian initiatives to improve air quality and reduce greenhouse gases (e.g., Ontario’s Drive Clean program to control vehicle emissions) [AI, C]
Link to original
F3.1
identify the major and minor chemical components of Earth’s atmosphere
Link to original