question_answer

  A teacher gave two test tubes, one containing water and the other containing sodium hydroxide solution, to the students and asked them to identify the test tube containing sodium hydroxide solution. Which substance can be used to identify the test tube? Give the test.   

Answer:

  Red litmus paper can be used because a base converts red litmus blue. Test Red litmus paper turns blue in sodium hydroxide solution as it is base.                                                          (1) While no change is observed in case of water as it is neutral.