JEE Main 2021 — Some Basic Concepts Of Chemistry Question with Solution
From: JEE Main 2021 (Online) 18th March Morning Shift
Question
Complete combustion of 3g of ethane gives x 1022 molecules of water. The value of x is __________. (Round off to the Nearest Integer). [Use : NA = 6.023 1023; Atomic masses in u : C : 12.0; O : 16.0; H : 1.0]
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Show full solutionCorrect answer: 18.069
Correct answer
18.069
Step-by-step explanation
Here, mol
From 1 mol C2H6 we get 3 mol H2O
From 0.1 mol C2H6 we get = 3 0.1 mol H2O
Moles of H2O = 0.3
= 0.3 6.023 1023 molecules
= 1.8069 1023 molecules
= 18.069 1022 molecules
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