Question

The color of methyl orange indicator in alkaline medium is:
A. Yellow
B. Green
C. Orange
D. Red

Answer 1

Hint:You can start by describing what pH indicators are, with some examples. Then describe titration briefly (a process where pH indicators are widely used). Then describe methyl orange, followed by its color change in acidic solution and basic solution.

Complete step by step solution:
> While starting the solution, we have to discuss what titration and pH indicators are.
- Titration – It is a technique used to calculate the concentration of an unknown solution by using another solution of known concentration.
- pH indicators – pH indicators are chemical compounds that are added in a solution in a very small amount, in order to determine the pH of the given solution.
pH indicators act as a detector of hydrogen ions or hydroxide ions . The most common type of pH indicators, indicate the pH of a substance by changing their colors, for example,
- Naphtholphthalein is a pH indicator that changes color to pale red in low pH solution and changes color to greenish-blue in high pH solution.
- Methyl orange is also a pH indicator that is very widely used in the process of titration because it shows a clear color variance for different pH values.
- Methyl orange shows a yellow color when it is mixed with an alkaline solution (a solution that is a mixture of base solids mixed with water, i.e. a basic solution) and shows a red color in an acidic solution.
Hence, option A is the correct option.

Note:Methyl orange should not be confused with methyl violet, methyl yellow, screened methyl orange (1st transition), screened methyl orange (2nd transition), methyl red and methyl purple. These are all pH indicators that have different structures, they also show different colors in low and high pH levels.