Multiple choice

Starchy food turns ______ on the addition of iodine solution.

  1. violet

  2. blue-black

  3. pink

  4. green

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The presence of any nutrient can be tested and confirmed by particular tests, e.g. presence of proteins can be tested by using copper sulphate and caustic soda. Oily patch on paper, when a food product is kept over it, confirms the presence of fats. The addition of iodine turns the starchy food to blue-black.