Teachers TryScience

i) By using Phenolphthalein indicator :

Take 5 ml of any one of the sample given. Add a drop of phenolphthalein indicator to the test tube containing sample. If the color is pink the sample taken is base. If there is no change in color means , the sample taken is acid.

ii) By using Methyl Orange indicator :

Take 5 ml of another sample in another test tube. Add a drop of methyl orange indicator. If the color is red, it is acid and if the color is yellow, it is base.

iii) By using Litmus papers:

Take 5 ml of sample solution in a test tube. Dip blue litmus paper in it.

* Acid turns blue litmus to red.

* Base, no change in blue color.

Like the same manner dip red litmus paper.

* Acid, no change in red litmus paper.

* Base turns red litmus to blue.

iv) By using Sodium bicarbonate :

Take 5 ml of sample solution and add small amount of sodium bicarbonate.

* If effervescence comes, Acid

* If no effervescence, Base

V) By using copper turnings :

Take 5 ml of sample solution in a test tube and add a small amount of copper turnings. If heat is required, heat the test tube.

* If bubbles come, Acid

* If no bubbles come, Base.