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How concentrated an acid is vinegar?. A simple titration experiment. The big idea. Acids and bases neutralize each other A base of known concentration can be used to determine the concentration of an unknown acid At the equivalence point, the moles of acid and base molecules are exactly equal
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How concentrated an acid is vinegar? A simple titration experiment
The big idea • Acids and bases neutralize each other • A base of known concentration can be used to determine the concentration of an unknown acid • At the equivalence point, the moles of acid and base molecules are exactly equal • Color change is the indication of equivalence
The reaction • Acids and bases neutralize each other • A base of known concentration can be used to determine the concentration of an unknown acid • At the equivalence point, the moles of acid and base molecules are exactly equal • Color change is the indication of equivalence
Each mole of NaOH neutralizes one mole of acetic acid • For a 1M solution, each mL is 0.001 moles of NaOH
When you add EXACTLY equal moles of NaOH, the phenopthalein will turn pink and STAY pink • the critical ONE DROP is the one that does it
Calibrate the dropper: How many mL in one drop? • Count the drops to fill a 4 mL cuvette
Results • What was your measured concentration of acetic acid in the vinegar? • How does this compare with what the bottle says?