Question

A drop of sodium hydroxide is added to blue litmus.

Answer 1

Answer:

Blue Litmus will change into red if it is added in sodium hydroxide. Hope you find this useful.

Answer 2

Answer:

When sodium hydroxide or caustic soda is poured on the blue litmus paper, the litmus paper remains unchanged.  

Explanation:

Litmus paper is a natural indicator. It is used in chemistry for pH identification. It has a unique characteristics, which it turns red in acidic medium, and blue in basic medium.

Sodium hydroxide in water solution produces strong base. This base, or the alkali turns red litmus blue. But the supplied litmus paper is blue.

So, there’s no change in colour. It remains unchanged.