Ignore the flea in the diagram above (not sure what it is....)
- Prepare the apparatus above
- Fill the burette with a known volume of acid (eg 100cm3)
- Fill the conical flask with a known volume of alkali
- Put an indicator in the conical flask (let's say you're using phenolphthalein)
- Using the tap, slowly drip the acid into the alkali, stirring every 10 seconds and watching carefully for the phenolphthalein to turn colorless (it's pink in alkalis) - this will mean that it's neutral. At this point, stop pouring in the acid immediately.
- Once it has turned colorless, see how much acid you've used up
- Repeat the process using the known volume of acid into the known volume of alkali without the indicator.
- Your solution is now neutral and not contaminated with indicator :) (If you did it right, which hopefully you did)
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