A gas evolves when carbonate is added to an acidic solution. If the gas turns lime water milky, which gas is it?
Answer and explanation
Correct answer: Carbon dioxide
A carbonate reacts with an acid to form a salt, water, and carbon dioxide: carbonate + acid → salt + H₂O + CO₂. Passing carbon dioxide through limewater produces insoluble calcium carbonate, which makes the liquid milky. Therefore option B is correct. Hydrogen, oxygen, and nitrogen do not give this characteristic limewater test under these conditions.
Frequently asked questions
What is the correct answer to this question?
Carbon dioxide
Why is this the correct answer?
A carbonate reacts with an acid to form a salt, water, and carbon dioxide: carbonate + acid → salt + H₂O + CO₂. Passing carbon dioxide through limewater produces insoluble calcium carbonate, which makes the liquid milky. Therefore option B is correct. Hydrogen, oxygen, and nitrogen do not give this characteristic limewater test under these conditions.
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.
