Lesson plan

Chemistry of plants and soil

Do soil tests, and understand the role that plants have in the nitrogen cycle.
Science content
Biology: Food Webs, Ecosystems, Biomes (3, 4)
Chemistry: Atoms, Molecules (3-7)
Earth/Space: Rock cycle, Earth Materials, Natural resources (5)

We will look at the chemistry of our environment.
What is chemistry? Everything is made up of molecules, too small to see, even the air.
Show model of molecules, made of atoms. We will show what is happening with the real molecules using these models. These molecules interact with each other, break apart and form other molecules.
We will look at the chemistry in soil and how living things use the soil molecules.

Walk to collect soil then back in the classroom, do soil tests.

Look at pH results and discuss how the pH changes (see soil test activity).

While the colour is developing for nitrogen test, use molecule models to look at the chemistry of nitrogen in the environment:
Nitrogen cycle with molecule models

Then look at nitrogen and phosphorus and potassium test results.
Discus importance of these other minerals (see soil test activity).

Many other minerals needed by plants.
We eat the plants and get these minerals too, and use them in our own chemistry.

Grades taught
Gr 6
Gr 7