If blue litmus turns red in a solution and electric current also passes through it, which conclusion is strongest?
Answer and explanation
Correct answer: The solution is acidic and contains ions
Blue litmus changing to red is the standard indicator test for an acidic medium. Passage of current through an aqueous solution requires mobile charged particles, usually ions, to carry charge between the electrodes. Combining both observations gives the strongest conclusion in option A: the solution is acidic and contains ions. A neutral solution can also contain ions, but options B, C, and D do not fit the stated observations.
Frequently asked questions
What is the correct answer to this question?
The solution is acidic and contains ions
Why is this the correct answer?
Blue litmus changing to red is the standard indicator test for an acidic medium. Passage of current through an aqueous solution requires mobile charged particles, usually ions, to carry charge between the electrodes. Combining both observations gives the strongest conclusion in option A: the solution is acidic and contains ions. A neutral solution can also contain ions, but options B, C, and D do not fit the stated observations.
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.
