Which pair is correct?
Answer and explanation
Correct answer: Washing soda — Sodium carbonate decahydrate
Washing soda is sodium carbonate decahydrate, Na₂CO₃·10H₂O, so option A gives the correct name and formula description. Bleaching powder is not sodium chloride; it is commonly represented as calcium oxychloride. Plaster of Paris is calcium sulphate hemihydrate, not calcium carbonate. Baking soda is sodium hydrogen carbonate, not calcium sulphate. Therefore only option A is correct.
Frequently asked questions
What is the correct answer to this question?
Washing soda — Sodium carbonate decahydrate
Why is this the correct answer?
Washing soda is sodium carbonate decahydrate, Na₂CO₃·10H₂O, so option A gives the correct name and formula description. Bleaching powder is not sodium chloride; it is commonly represented as calcium oxychloride. Plaster of Paris is calcium sulphate hemihydrate, not calcium carbonate. Baking soda is sodium hydrogen carbonate, not calcium sulphate. Therefore only option A 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.
