Adding sodium carbonate to a solution gives no gas, but adding acid to sodium carbonate gives gas. What does this indicate?
Answer and explanation
Correct answer: Sodium carbonate needs an acidic medium to release gas
Carbonate ions release carbon dioxide when they react with hydrogen ions supplied by an acid: carbonate plus acid produces a salt, water, and CO2. Merely adding sodium carbonate to a solution that is not acidic need not produce visible gas. Thus option A correctly identifies the need for an acidic reaction medium. The gas is carbon dioxide, not hydrogen; sodium carbonate is soluble and is an ionic salt rather than a metal.
Frequently asked questions
What is the correct answer to this question?
Sodium carbonate needs an acidic medium to release gas
Why is this the correct answer?
Carbonate ions release carbon dioxide when they react with hydrogen ions supplied by an acid: carbonate plus acid produces a salt, water, and CO2. Merely adding sodium carbonate to a solution that is not acidic need not produce visible gas. Thus option A correctly identifies the need for an acidic reaction medium. The gas is carbon dioxide, not hydrogen; sodium carbonate is soluble and is an ionic salt rather than a metal.
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.
