An organic compound has 42.1\% carbon, 6.4\% hydrogen and remainder is oxygen. If its molecular weight is 342, then its…
Some Basic Concepts (Mole Concept) · Class 11 · JEE Main Previous Year Question
An organic compound has carbon, hydrogen and remainder is oxygen. If its molecular weight is , then its molecular formula is:
- a
- b
- c✓
- d
🧠 Use the molecular weight to get atom counts directly Total mass per molecule . Take as carbon, as hydrogen, the rest as oxygen, and divide by atomic masses.
🗺️ Three counts C atoms: . H atoms: . O atoms: .
So the formula is — which is sucrose.
⚡ Speed scan is the textbook fingerprint of disaccharides (sucrose, lactose, maltose). All three share . Recognise it on sight.
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