In this session we will start to investigate the question –
- What is in the air we breath?
What should I be able to do at the end of this investigation? I should be able to …
- Construct different types of data displays and predict patterns.
- Describe and interpret different data sets.
- Communicate ideas, explanations and processes in a variety of ways, including multi-modal texts.
- Compare fractions with related denominators
- Make connections between fractions, decimals and percentages
- Calculate the mean, median and mode of a data set.
- Describe what ‘air’ is made up of.
To answer this question we are going to do two experiments. The first experiment we are going to set up today so that we can look at the results in a few days time.
You will need.
- black permanent marker
- milk carton
- hole punch
- magnifying lens
- digital camera
What to do.
1. Cut the carton into four flat pieces by cutting along the side seams of the carton. Cut each side into 3 square pieces, each piece will be approximately 7cm long and 7cm wide. You will have a total of 12 squares when you are done.
2. Using the hole punch, punch a hole in one corner of each square.
3. Tie a piece of string through the hole to make a loop for hanging the square up, on a tree branch for example.
4. Make a data sheet in Excel to record where you place your squares, and what data you later will collect from them:
5. Write the name of each location in your data table. Decide on your four locations. They can be anywhere within school ground. The best locations will be places where other students are not going to interfere with them.
6. Using your black permanent marker, draw a 2.5cm by 2.5cm box in the centre of the white side (what used to be the inside of the carton) of each square. On the other write “Science Experiment – please do not disturb”.
7. Write the name of the location on the bottom of each square, you will use three squares for each location.
8. At each location, find a place to hang up three of your collection squares. You can hang the squares from a tree branch, sign post, light post, or any other safe landmark. When tying them up make sure that the three squares do not touch each other.
9. Before you hang each square up, spread a thin layer of vaseline in the black box in the centre of each square with your finger. Hang up the collection square.
10. Leave your collection squares for 3–5 days.
11. After you have waited, it is time to collect your data from the squares.
12. Revisit each location bringing your data table, magnifying glass and a digital camera.
13. Remove the squares one at a time. Each time, use your magnifying glass to count the number of visible particles you see stuck in the Vaseline inside the boxed area. Write the number in your data table.
14. Take a picture of the square.
15. Proceed to the next square and/or location until you have collected all of your data and filled out your data table.
16. For each location you will have collected three sets of data, so you will want to average the data to get a better result. First add together the three counts and write the answer in the “TOTAL” box. Then divide this number by 3 and write the answer in the “Average” box.
17. Now you are ready to make a graph of your data. Make a bar graph by writing a scale for the number of particles on the left side (y-axis) and then by drawing a bar up to the correct number of particles for each location. Remember to label each bar of your graph, or make a colour key.
18. Which sites had the most particulate matter in the air? Is this what you expected? Were each of your three counts the same or different? What do you think this tells you about the relative air quality at each location?
19. In your blog start a new entry entitled “Air particles and quality”. Firstly, write a sentence stating what the purpose of the experiment was. Next, include your data table followed by one picture from each location. Finally answer the questions above. Remember to answer them in complete sentences.
Experiment adapted from http://www.sciencebuddies.org/science-fair-projects/project_ideas/EnvSci_p009.shtml#procedure
Activity 2. The contents of air.
Experiment adapted from http://www.plantscafe.net/modules/b_book_engl_t1_m1.pdf
Okay, so we know a little about what’s in air but how does that change the further you travel from the surface?