Fa.ara
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Hi can some help me answer this question pls

Phenolphthalein is an indicator that is pink in alkaline solutions.
When the pH drops below pH 8.3 phenolphthalein goes colourless. When phenolphthalein is added to milk it turns pink.
Suggest why, when lipase is added to a milk solution containing phenolphthalein, a colour change from pink to colourless is observed. (1 mark)
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Glow72778826
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When lipase breaks down the lipids (fats) in the milk, the pH of the milk decreases so it turns colourless
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Fa.ara
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(Original post by Glow72778826)
When lipase breaks down the lipids (fats) in the milk, the pH of the milk decreases so it turns colourless
thnx
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Glow72778826
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Your welcome! I’ve recently just learnt about the decay practical in Biology so I managed to remember the answer 😅
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Hufflepuffle17
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It goes colourless because of lipase breaking down the milk and making it less alkaline than before
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khanj471.202
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Here, an alkaline solution of milk, lipase and phenolphthalein will change from pink to colourless as the fat in milk is broken down to form fatty acids (and glycerol) thus reducing the pH to below 8.3. The time taken for this reaction to occur is affected by temperature.
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terrificfunx
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Use Revision Nova, if you get one of their plans, you can email them questions and they'll do it for you
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