Question

from which substances natural indicators are prepared? Explain any one in detail with procedure.​

Answer 1

Explanation:

natural indicators are prepared from

• Turmeric
• Purple cabbage

Answer 2

Answer:

Natural Indicator is a type of indicator that can be found naturally and can determine whether the substance is an acidic substance or a basic substance. Some examples of natural indicators are red cabbage, turmeric, grape juice, turnip skin, curry powder, cherries, beetroots, onion, tomato, etc

Explanation:

To prepare a natural indictor:

Select a suitable coloured plant material, such as purple cabbage.

Extract the colour from the plant material by either:

Boiling it in water.

Crushing it with water or alcohol using a mortar and pestle.

Decant the solution from the solid.

To test a natural indicator:

Dip the ends of two strips of filter paper into the indicator and allow to dry.

Using an eyedropper, apply a drop of strong acid to one strip and a drop of strong base to the other strip.

Record any changes in colour.

Add additional drops of acid and base to the strips until no further changes in colour are observed.

If an indicator is prepared from purple cabbage, the following colours should be observed:

Initial/Neutral colour: Purple

Colour when exposed to strong acid: Pink, then Red

Colour when exposed to strong base: Blue-Green, then Yellow

Purple cabbage