← 2.2 Acids, Bases and Indicators
What bases are
Integrated Science · Grade 7 · about 40 minutes
A base turns red litmus blue. Dilute bases often feel soapy. Ash, soap, lime and toothpaste are everyday bases. Alkalis dissolve in water.
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- 8 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
Other lessons in this sub-strand
- Why acids and bases matter
- What acids are
- What bases are
- Acids in the Kenyan kitchen
- Bases: ash, soap and lime
- How to use litmus paper
- Identifying acids with litmus
- Identifying bases with litmus
- Neither acid nor base
- Plant indicators
- Preparing a plant indicator
- Classifying with a plant indicator
- Universal indicator and pH
- Physical properties of acids
- Physical properties of bases
- Investigating properties together
- Acids fizz with baking soda
- Uses of acids
- Uses of bases
- Indicators and antacids
- Soil acidity and lime
- Waste, safety and appreciation