What is the colour of methyl orange in acidic solution and why is it useful?
Answer and explanation
Correct answer: Red because it helps identify acid
The governing concept is the colour change of an acid–base indicator. Methyl orange is red in an acidic solution and changes through an orange transition range toward yellow in an alkaline solution. Because the colour depends on the solution’s pH, it helps distinguish acidic and alkaline conditions during testing or titration. Option B describes its alkaline colour incompletely, while C and D give incorrect colours and interpretations. Therefore A is correct.
Frequently asked questions
What is the correct answer to this question?
Red because it helps identify acid
Why is this the correct answer?
The governing concept is the colour change of an acid–base indicator. Methyl orange is red in an acidic solution and changes through an orange transition range toward yellow in an alkaline solution. Because the colour depends on the solution’s pH, it helps distinguish acidic and alkaline conditions during testing or titration. Option B describes its alkaline colour incompletely, while C and D give incorrect colours and interpretations. Therefore A is correct.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
