Question

In an experiment to measure the pH values of solutions, a student placed strips of universal indicator paper in four beakers containing solutions A, B, C and D. The colour of universal indicator paper in these solutions is as shown below :

The solution having lowest pH value is:
(1) A
(2) B
(3) C
(4) D

Answer 1

The universal indicator shows a wide range of colour differences in acids, bases, and neutral solutions. For strong acids, it shows a red colour, for moderate acids it changes from orange to yellow. Bases change from blue to indigo. On the pH scale, acids have the lowest value. So, solution C has the lowest pH as it is the strongest acid out of the given options.

Hence, the correct answer is option 3.