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The diagram below shows a molecule of maltose. |
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This molecule can be broken into two glucose
molecules by a chemical reaction |
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(a) |
(i) |
What type of reaction would this be |
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Hydrolysis |
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(1) |
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(ii) |
What substance would need to be added for this
reaction to proceed |
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Water |
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(1) |
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(iii) |
Draw below one of the glucose molecules that
would be formed by this reaction |
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(1) |
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(b) |
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Describe how you would perform a test to indicate that a
substance contained sucrose and not glucose |
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First show glucose
(a monosaccharide) is not present
- Add Benedicts solution
- Blue colour when
heated shows no glucose present
Then show a maltose
(a disaccharide) is present
- Warm a sample with
dilute HCl
- Neutralise
- Add Benedicts solution
- Red/Brown colour
on heating shows disaccharide present
NOTE score a max of
2 bullet points in each section |
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(4) |