1. Property of matter
1. Acidity and alkanity

2. What is an acid Has a pH lower than 7 Is sour and sharp-tasting
Reacts with metals
Turn litmus paper red.
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This Photo by Unknown Author is licensed under CC BY-SA

3. What is a base Has a pH higher than 7 Taste bitter and harsh
Is slippery to the touch
Does not react with metals
Turn litmus paper blue
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This Photo by Unknown Author is licensed under CC BY-NC

4. What is a neutral substance
Has a pH of 7
Does not change the colour of litmus paper
What is a neutral substance

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6. The pH scale is a logarithmic scale

7. How to know if a substance is acid or basic?
litmus paper
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8. How to measure pH? pH paper
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9. How to measure PH (2) Universal indicator
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