You are provided with three test tubes A, B, C which contain distilled water, acidic and basic solutions. If you are given blue litmus paper only, how will you identify the nature of the solutions in three test tubes?
Put the blue litmus paper in each of the three test tubes. The test tube which changes the blue litmus to red is an acidic solution.
No the litmus which turned red by acidic solution can be used to test for basic solution.
Dip the red litmus in the two test tubes. The test tube which change the red litmus back to blue colour is basic solution and the solution which shows no change to litmus colour is distilled water.