Which of the following indicators turns from yellow to red when added to an acidic solution?
Answer
Methyl orange
The correct answer is Methyl orange — Hence the correct option is Methyl orange.
Step-by-step solution
- Identify the indicator that is yellow in neutral solution and turns red in acidic conditions.
- Methyl orange is yellow above pH 4.4 and turns red below pH 3.1, matching the description.
- Hence the correct option is Methyl orange.
Common mistake: Choosing phenolphthalein, which turns pink in basic solution instead of red in acid.
Concept tested: Indicators
Published · How this solution was prepared and checked
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