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CLIP 13510

Acids and Alkalis

Acids and Alkalis

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Key Info
  • Acids and Alkalis
  • Science presenter Jon Chase uses universal indicator to measure the pH of a solution. Different pHs within different parts of the body are briefly described. The pH of the oceans is slightly alkaline but the increase in carbon dioxide in the atmosphere is acidifying them. This is demonstrated in the lab by adding dry ice to an alkaline solution containing universal indicator and explaining the pH changes.
  • Subject:



    Chem: Chemical Reactions

  • Keywords: Acid, alkali, pH, neutralisation, oceans, corals, fish, dry ice, carbon dioxide, CO2, BitesizeScience
Ideas for use in class
  • Students could test the pH of fresh and sea water from different sources, both using universal indicator and a pH probe. Sea water could be taken from a nearby coastline, or mixed up using synthetic salt mix available from aquatic retailers. As an alternative to the demonstration using dry ice, this could be repeated with universal indicator and water in a conical flask with a student exhaling into it slowly through a straw (wearing eye protection). The effect of ocean acidification on coral reefs could be researched and investigated using calcium carbonate in the lab.
Background details
  • Clip language : English
  • Aspect ratio : 16x9

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