JEE Main 2023 — S Block Elements Question with Solution
From: JEE Main 2023 (Online) 10th April Evening Shift
Question
Number of water molecules in washing soda and soda ash respectively are :
Choose an option
Show full solutionCorrect option: D
Step-by-step explanation
- Washing soda is a hydrated form of sodium carbonate, with the chemical formula Na2CO3·10H2O. This means that each molecule of washing soda contains 10 water molecules.
- Soda ash is the anhydrous form of sodium carbonate, with the chemical formula Na2CO3. This means that it does not contain any water molecules.
Soda ash is typically produced by heating washing soda to drive off the water molecules. Washing soda can be produced by dissolving soda ash in water and then recrystallizing it.
The correct answer is Option D: 10 and 0.
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This is a previous-year question from JEE Main 2023, covering the S Block Elements chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.