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?
Litmus papers are indicators that differentiate between acidic, basic and neutral solutions. Red litmus changes to blue with basic solution If the colour of red litmus paper gets changed to blue, then it indicates that the given solution is a base and if there is no colour change, then it is either acidic or neutral. Whereas blue litmus turns to red with acidic solution. If the colour of blue litmus paper gets changed to red, then it indicates that the given solution is a acid and if there is no colour change, then it is either basic or neutral. This can be best explained by a simple experiment. Let's take 3 test tubes and labelled as A, B, and C which contain water, acidic and basic solutions respectively by using litmus paper test. We confirm that test tube A does not show any change in that indicates it is not acid and base. Test tube B also does not show any change in litmus paper. Only test tube C changes red litmus to blue indicating the solution is base.
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