JEE Main 2021 — Some Basic Concepts Of Chemistry Question with Solution
From: JEE Main 2021 (Online) 27th July Morning Shift
Question
The density of NaOH solution is 1.2 g cm3. The molality of this solution is _____________ m. (Round off to the Nearest Integer)
[Use : Atomic mass : Na : 23.0 u, O : 16.0 u, H : 1.0 u, Density of H2O : 1.0 g cm3]
[Use : Atomic mass : Na : 23.0 u, O : 16.0 u, H : 1.0 u, Density of H2O : 1.0 g cm3]
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Show full solutionCorrect answer: 5
Correct answer
5
Step-by-step explanation
Consider 1 litre solution
mass of solution = (1.2 1000)g = 1200 gm
Neglecting volume of NaOH
Mass of water = 1000 gm
Mass of NaOH = (1200 1000)gm = 200 gm
Moles of NaOH = mol
molality = m
mass of solution = (1.2 1000)g = 1200 gm
Neglecting volume of NaOH
Mass of water = 1000 gm
Mass of NaOH = (1200 1000)gm = 200 gm
Moles of NaOH = mol
molality = m
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