Question

What is the colour of `"methyl orange"` in basic solution?

Answer 1

It should be bright yellow.

Explanation:

Methyl orange has a `pK_a = 3.47`. In aqueous solution the indicator should be bright yellow in colour at `pH` `>` `4`..

Answer 2

Bright yellow.

Explanation:

Methyl orange is a pH indicator that is red in acidic medium and yellow in alkali medium.

More specifically, methyl orange is red in solutions that have a pH that's lower than `3.1` and yellow in solutions that have a pH that's higher than `4.4`.


Since potassium hydroxide, `"KOH"`, is a strong base, the pH of the solution will be higher than `7`, which of course implies that adding methyl orange to the solution would change its color to bright yellow.