Methyl red is a common acid-base indicator.It has a K_a equal to 6.3 × 10^-6.Its un-ionized form is red and its anionic form is yellow.What color would a methyl red solution have at pH = 7.8?

Question

Quizplus · Accepted Answer

Methyl red has an acidic range of 4.4-6.2, where it appears red. At a pH of 7.8, which is basic, it would be above its acidic range and its anionic form would predominate, giving it a yellow color. Therefore, the correct answer is D) yellow.

Methyl Red Is a Common Acid-Base Indicator