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JEE Main202522 Jan 2025Evening ShiftChemistrySome Basic Concepts of ChemistryActual

Density of 3 M NaCl solution is 1.25 ~g / mL . The molality of the solution is :

Options

  1. A1.79 m
  2. B2.79 m
  3. C2 m
  4. D3 m

Correct answer

B. 2.79 m

Step-by-step solution

aligned & 3 M NaCl , d _ sol =1.25 gm / mol & aligned Molality & = M 1000 1000 ~d - M M _ W & = 3000 1250-175.5 =2.79 aligned aligned

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