Question

Baking soda turns:
(A) Turmeric to red
(B) Purple cabbage juice to green
(C) Red litmus to blue
(D) All of the above

Answer 1

Hint: Chemical indicator is widely used in chemistry to identify the compound whether it is acidic in nature or basic in nature. Indicators used for this purpose must give some visual changes like change in colour which is easily detected.

Complete Step By Step Answer:
Baking soda is basic in nature due to the presence of bicarbonate and has a value around $ 8 $ .
Turmeric is a natural herb which contains a chemical compound known as curcumin. When turmeric is treated with base it will change to red and it turns yellow when treated with acidic water. As we know baking soda is a base and when it reacts with curcumin it turns it into red colour due to its interaction with curcumin.
Purple cabbage juice interacts with basic compounds to change its colour into green. We already discussed that baking soda is basic in nature and when it is mixed with juice of cabbage which is initially purple in colour turns into green.
As we know when red litmus paper comes in contact with a base it will turn into red. So due to basic nature when a strip of blue litmus paper dipped into baking soda solution it will change into red.
 $ \Rightarrow $ From the above discussion we conclude that Baking soda turns Turmeric to red, Purple cabbage juice to green as well as Red litmus to blue.
Therefore, option $ \left( Option: D\right) $ is the correct option.

Note:
There are a wide variety of indicators used which have different colours in acidic and basic solution. Methyl orange is red in acidic solution and turns yellow in basic solution, phenolphthalein is colorless in the case of acidic solution while turning pink in basic solution.