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Neutralisation with an indicator

Turn a pink base colourless by adding acid, and watch the temperature rise.

Topic: Acids, bases and saltsGrade: 11Free

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What you do

  1. Add phenolphthalein to the sodium hydroxide.
  2. Add hydrochloric acid, 5 mL at a time, until the pink colour disappears.
  3. Read the thermometer: how much did the temperature rise?
  4. By how many °C did the temperature rise?

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