Acids have a pH below 7 and examples include citric acid and hydrochloric acid. The strongest acids have a pH of 0 or 1 while the weakest acids have a pH of around 5. Strong acids are colored while weak acids are colorless. Alkalis have a pH above 7 and examples include sodium hydroxide and ammonia. The strongest alkalis have a pH of around 14 while the weakest alkalis have a pH of around 9. Strong alkalis are also colored while weak alkalis are colorless. Neutralization reactions occur when an acid and alkali are mixed together, forming a salt and water. Common indicators, such as litmus paper, can be used to test whether

1. Acids and Alkalis
Give examples of industrial and domestic alkali
Acids _______________________________________________________
What are acids? _______________________________________________________
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What pH is the strongest/weakest acid? Neutral solutions
_______________________________________________________ What is a neutral solution? What colour/pH is a neutral solution?
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What colour is the strongest/weakest acid? _______________________________________________________
_______________________________________________________ Examples ________________________________________________
_______________________________________________________ What are neutralisation reactions?
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What is the range for the pH of acids? _______________________________________________________
_______________________________________________________ Give examples of everyday neutralisation reactions
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Give examples of industrial and domestic acids. _______________________________________________________
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_______________________________________________________ Indicators
_______________________________________________________ What are indicators? give examples
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Alkalis What can be used as a natural indicator?
–What are alkalis? _______________________________________________________
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_______________________________________________________ Hazard signs and safety procedures
What pH is the strongest/ weakest alkali? Draw a hazard sign for a weak and a concentrated acid.
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What colour is the strongest/weakest alkali? How can you dilute an acid or an alkali to make them less concentrated and
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What is the pH range for alkalis? What should you do if you spill acid on your skin?
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