You have been provided with three test tubes, one of them contains distilled water and the other two contain an acidic solution and a basic solution respectively. If you are given only red litmus paper; how will you identify the contents of each test tube?

Separately, sprinkle a few drops of solution from each test tube onto the red litmus paper.
Basic solution is in the solution that turns red litmus blue.
Test the liquids in the other two test tubes with this blue litmus paper.
The acidic solution comes from the test tube that turns blue litmus paper red, while the watery solution comes from the test tube that doesn’t change either red or blue litmus paper
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Final Answer :
Litmus paper is unaffected by distilled water. A red litmus paper will remain red in distilled water, but a blue litmus paper would remain blue only.