Water Chemistry

What this page covers

Water Chemistry is a focused set of resources, and most of them are mind maps. They follow three threads: hard and soft water, how water is made safe to drink, and how waste water is treated. Several resources mention GCSE Chemistry or IGCSE Chemistry, so the material suits school students at that stage.

Where to start

Begin with a mind map. The Hard and Soft water map explains that hard water contains calcium and magnesium ions, and that the hardness can be temporary or permanent. The map called Purifying and Testing Water lists water sources such as lakes, rivers, reservoirs and aquifers, then what water is used for.

Next, move to the process side. The flowchart Waste Water Treatment GCSE Chemistry walks through screening and grit removal, then sedimentation, which produces sewage sludge and effluent.

A sensible order

1. Read one or two mind maps on hard and soft water.
2. Work through a flashcard deck such as Chemistry: hard and soft water, which asks what hard water contains and what it forms with soap.
3. Look at treatment with the Water flashcard deck, which covers coagulation, flocculation, chlorination, zeolites and water softeners.
4. Finish with a quiz.

Using quizzes and maps together

Use a map first to see how ideas connect, such as scum, scale and lather. Then take a quiz and note which questions you missed. Go back to the matching branch of the map and read it again. The O654 C11 Air & Water Quiz includes a calculation about the oxygen in air, which makes it a good test of working as well as recall. Other quizzes here are labeled with AQA and GCSE Chemistry, so teachers can pick one that fits their class.

Where it fits

This unit sits in the strand Earth, Environment and Applied Chemistry, within Chemistry. Pick a resource that matches what you are studying this week, and then try making a map of your own to check you can explain it.