In which reaction is a gas most likely to form that turns lime water milky?
Answer and explanation
Correct answer: Sodium carbonate and dilute acid
The governing test is that carbon dioxide turns limewater milky because it reacts with calcium hydroxide to form insoluble calcium carbonate. An acid reacting with a carbonate releases carbon dioxide: sodium carbonate + dilute acid → salt + water + CO₂. Zinc with dilute acid mainly releases hydrogen, while sodium hydroxide with water and common salt with water do not produce carbon dioxide. Therefore, option B is correct.
Frequently asked questions
What is the correct answer to this question?
Sodium carbonate and dilute acid
Why is this the correct answer?
The governing test is that carbon dioxide turns limewater milky because it reacts with calcium hydroxide to form insoluble calcium carbonate. An acid reacting with a carbonate releases carbon dioxide: sodium carbonate + dilute acid → salt + water + CO₂. Zinc with dilute acid mainly releases hydrogen, while sodium hydroxide with water and common salt with water do not produce carbon dioxide. Therefore, option B 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.
