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Molality ( ( m ) ) of (3 M ) aqueous solution of ( NaCl ) is : (Given : Density of solution (=1.25 ~g ~mL ⁻¹ ), Molar mass in ( g mol ⁻¹: Na -23, Cl -35.5 ))

Options

  1. A(1.9 ~m )
  2. B(3.85 ~m )
  3. C(2.79 ~m )
  4. D(2.90 ~m )

Correct answer

C. (2.79 ~m )

Step-by-step solution

3 moles are present in 1 litre solution molality = 3 1000 1.25 1000-[3 58.5] =2.79 ~m

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