If the density of some lake water is 1.2 | Class 12 Chemistry Chapter Solutions, Solutions NCERT Solutions

Question:

If the density of some lake water is 1.25 g mL-1 and contains 92 g of Na+ ions per kg of water, calculate the molality of Na+ ions in the lake.

Answer:

We know molality = moles of solute / mass of solvent in kg

Now mass of Na+ ions = 92 g (given)

Moles of Na+ ions = 92 / 23 = 4

And mass of water = 1kg

Therefore molality = 4/1 = 4m


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Comments

  • Shyam Sunder
  • 2019-03-27 18:54:52

why density is mentioned?


Comment(s) on this Question

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 2 , Question 26: If the density of some lake water is 1.25 g mL-1 and contains 92 g of Na+ ions per kg of water, calc....