Phenolphthalein is a colourless indicator that turns pink in basic solution.
Question 4
Phenolphthalein is a synthetic indicator and its colours in acidic and basic solutions, respectively are (a) red and blue. (b) blue and red. (c) pink and colourless. (d) colourless and pink
Name an indicator which is pink in alkaline solution but turns colourless in acidic solution.