A bulb glows in an aqueous acid but not in dry acidic gas. What is the correct reason?
Answer and explanation
Correct answer: Mobile ions are produced in the presence of water
An electric current in a solution requires mobile charged particles. An acid dissolved in water ionises, producing ions such as H₃O⁺ and a negative counter-ion that can move through the solution and carry charge, so the bulb glows. Dry hydrogen chloride gas does not provide freely moving ions in the same way, so it does not conduct sufficiently. Hence option A is correct; the other statements contradict ionic conduction.
Frequently asked questions
What is the correct answer to this question?
Mobile ions are produced in the presence of water
Why is this the correct answer?
An electric current in a solution requires mobile charged particles. An acid dissolved in water ionises, producing ions such as H₃O⁺ and a negative counter-ion that can move through the solution and carry charge, so the bulb glows. Dry hydrogen chloride gas does not provide freely moving ions in the same way, so it does not conduct sufficiently. Hence option A is correct; the other statements contradict ionic conduction.
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.
