Question

you have been provided with three test tubes one of them contains distilled water and other to contain an acidic solution and a basic solution respectively if you are giving only red litmus paper how will you identify the contents of each test tube

Answer 1

First dip the red litmus paper in all the solutions. The solution which turns the litmus paper blue is basic solution.
Then put the resulted blue litmus in solutions and if turn back to red then that solution will be acidic. the left solution is water

Answer 2

Explanation:

If the colour of red litmus does not change then it is acid. If the colour of red litmus changes to blue then it is base. If there is slight change in the colour of red litmus (such as purple) then it is distilled water.