Science
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?
Answer
We take three pieces of red litmus paper. The solution which turns red litmus paper to blue is basic solution. Distilled water (neutral) and acidic solution will not effect red litmus paper.
Now we divide the so formed blue litmus paper into two pieces. The test tube containing distilled water does not change the colour of the blue litmus paper.
The test tube containing acidic solution changes the colour of the blue litmus paper to red. Hence, we can identify the three solutions.
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