JEE Main 2019 — Some Basic Concepts Of Chemistry Question with Solution
From: JEE Main 2019 (Online) 9th April Evening Slot
Question
What would be the molality of 20% (mass/
mass) aqueous solution of KI?
(molar mass of KI = 166 g mol–1)
(molar mass of KI = 166 g mol–1)
Choose an option
Show full solutionCorrect option: A
Correct answer
A1.51
Step-by-step explanation
20% (mass/
mass) aqueous solution means,
100 g solution contains 20 g KI
Mass of solvent = 100 – 20 = 80 g
So, 20 g of KI present in 80 g of solvent.
moles of KI present in 80 g of solvent.
We know,
Molality (m) =
m = = 1.51
100 g solution contains 20 g KI
Mass of solvent = 100 – 20 = 80 g
So, 20 g of KI present in 80 g of solvent.
moles of KI present in 80 g of solvent.
We know,
Molality (m) =
m = = 1.51
Practice this on the real CBT interface
Solve this JEE Main question (and the rest of the Some Basic Concepts Of Chemistry chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.
Solve interactively →About this question
This is a previous-year question from JEE Main 2019, covering the Some Basic Concepts Of Chemistry 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.