.Which test shows a positive result with a colour change of blue to purple?
Question
.Which test shows a positive result with a colour change of blue to purple?
Solution
The test that shows a positive result with a colour change from blue to purple is the Benedict's test for reducing sugars. Here are the steps:
- Add Benedict's reagent (blue solution) to the sample.
- Heat the mixture in a water bath.
- If the sample contains reducing sugars, the solution will change color from blue to green, yellow, orange, and finally to brick red or purple depending on the concentration of the reducing sugar.
- A purple color indicates a high concentration of reducing sugars.
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