Question

At PH=10, the metal dye complex has the colour ________

(a) Wine red

(b) Blue

(c) Green

(d) Pink

The question was posed to me in a national level competition.

I need to ask this question from Estimation of Hardness topic in division Water of Applied Chemistry

Answer 1

Right answer is (a) Wine red

Easiest explanation: At the PH=10, the metal dye complex ion has the colour is wine red but the dye itself has the blue colour at the PH of 10.