The gas formed on heating baking soda is passed through lime water. What will happen?
Answer and explanation
Correct answer: Lime water will turn milky
The governing concept is the test for carbon dioxide. On heating, sodium hydrogen carbonate decomposes: 2NaHCO₃ → Na₂CO₃ + CO₂ + H₂O. The released CO₂ reacts with calcium hydroxide in lime water to form insoluble calcium carbonate, CaCO₃, which makes the solution milky. Thus option A is correct; blue colour and a hydrogen pop test are unrelated.
Frequently asked questions
What is the correct answer to this question?
Lime water will turn milky
Why is this the correct answer?
The governing concept is the test for carbon dioxide. On heating, sodium hydrogen carbonate decomposes: 2NaHCO₃ → Na₂CO₃ + CO₂ + H₂O. The released CO₂ reacts with calcium hydroxide in lime water to form insoluble calcium carbonate, CaCO₃, which makes the solution milky. Thus option A is correct; blue colour and a hydrogen pop test are unrelated.
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.
