Curriculum
Science — Second Preparatory
Unit 1: Matter and Energy
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Unit 2: Matter and Chemical Reactions
0/6
Unit 3: Energy Flow in Photosynthesis and Respiration
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Unit 4: Geological Processes
0/4
Text lesson
Chemistry of Nutrition
Chemistry of Nutrition
Tests for nutrients
Tests for nutrients
| Nutrient | Test | Result that shows its presence |
|---|---|---|
| Glucose (a reducing sugar) | Benedict’s solution, heated | A brick-red precipitate forms |
| Starch | Iodine solution | The colour changes to blue-black |
| Proteins |
|
The colour changes to violet |
| Fats | Put a drop of the substance on filter paper and let it dry | A permanent translucent spot remains on the paper |
- When doing these tests
- compare the result with a sample of distilled water
- to be sure the colour change comes from the food and not from the water.
Chemistry of Nutrition · 3 / 7