A student prepares solutions of (i) an acid and (ii) a base


A student prepares solutions of (i) an acid and (ii) a base in two separate beakers. She forgets to label the solutions and litmus paper is not available in

the laboratory. Since both the solutions are colourless, how will she distinguish between the two ?


Phenolphthalein and methyl orange are also acid-base indicators. They can be used in place of litmus.

Procedure : Transfer a portion of the colourless solutions to two glass tubes. Add one or two drops of henolphthalein indicator to these. An acid

solution will remain colourless while the solution of base will ecome pink. Now, repeat the experiment with methyl orange indicator. In acid

solution, the indicator will become reddish while in base, it will be yellowish.

Leave a comment


Click here to get exam-ready with eSaral

For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.

Download Now