Module 4 Intro

1. Module 4 Intro

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Lesson 5

Module 4—Properties of Solutions

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Discuss

A photograph of water being released from a large pipe into a stream.

Photograph of a young woman holding a fish in one hand and her nose with her other hand.

Historically, people believed that diluting any type of substance renders it permanently harmless. A foul odour that dissipates no longer smells bad, and red food dye poured into a vast body of water will eventually vanish. But do these substances really disappear? Use relevant chemical concepts to explain how the dilution of a substance is not a way to treat pollution.

If “The solution to pollution is NOT dilution,” then what processes can be used to treat waste? Consider what you have learned in this lesson about dissolving, solubility, and solutions. Is it a good strategy to dilute solutions containing harmful substances?

Share your thoughts with your teacher or other students using your class discussion area.