If the pH of a solution is 3.5, what colour will be shown by each of the following indicators in the solution?

a)Methyl Violet
b) methyl red
c) Methyl orange
d) phenolphthalein

My answers:
a) Yellow to Blue
b) Red to Yellow
c) Red to Yellow
d) close to a light pink almost colourless.

1 answer

I don't believe you have interpreted the question correctly. For example,
for methyl red at pH 3.5. I look in my text and I see MR changes in the range of 4.2 to 6.3 (R-Y); below pH 4.2 it will be red and above 6.3 it will be yellow. Therefore, I would answer that at pH = 3.5 MR would be red.