Question

Three liquids are given to you. One is hydrochloric acid, another is sodium hydroxide and third is a sugar solution. How will you identify them? You have only one turmeric indicator.

Answer 1

HINT: Turmeric indicator turns red in a basic solution whereas remains yellow in acidic and neutral solution. Identify the acidic, basic and the neutral solution among the given solutions and accordingly answer for each.

COMPLETE STEP BY STEP SOLUTION: Before answering this question, let us understand what an indicator is and how the indicator given to us i.e. turmeric works.
We know that in chemistry, we use indicators for the determination of the pH of a solution. Different indicators work differently in acidic, basic and neutral solutions.
Here, turmeric indicator is given to us. Turmeric is yellow in acidic and neutral solution and turns bright red in basic solution.
Here we have three solutions. One is hydrochloric acid which is acidic another is sodium hydroxide which is base thus, the solution is basic and lastly we have a sugar solution which will be neutral.
To identify these solutions, firstly we will place turmeric in the given solution and the solution in which it turns red will be the base i.e. sodium hydroxide.
The, we will add the base in the other two solutions i.e. hydrochloric acid and the sugar solution.
The turmeric in the sugar solution will turn red upon addition of sodium hydroxide as the solution will turn basic.
Whereas the turmeric in the hydrochloric solution will undergo no change as the solution will become neutral upon addition of the base and turmeric is yellow in acidic as well as neutral solution.
Thus, this way we can identify the three solutions and this is the required answer.

NOTE: In chemistry we use indicators during titration to mark the end point of a titration. We see that in acid-base titrations, generally the end is marked by the change in colour of the solution. Depending upon the titration, it is very important for us to choose suitable indicators which will indicate the equivalence point.