What is the color of methyl orange in acids and alkalis?

Methyl orange is a pH indicator. A pH indicator is a substance that changes colour when added to an acid or alkaline solution. Methyl orange is used in titrations because its color change is clear and unambiguous. Methyl orange is red in an acid and yellow in an alkali.

Alkaline solutions have a pH higher than 7.0, while acid solutions have a pH less than 7.0. Methyl orange is more commonly used for titration of strong acids because of its distinct color change to red below a pH of 3.1. As the solution becomes less acidic, its color moves from red to orange. At a pH above 4.4, it turns yellow. This implies the red color change will not be observed in weaker acids with higher pH.