Question

Molarity of aqueous solution of NaOH solution is 4 M and density of solution is 1.2 gm/mL, the
Molality of solutions will be

Who give ans quickly i will mark him as brillianist

Answer 1

Answer: 3.84

Explanation:

Assume that u have 1 lt. of solution..

Multiply 1 lt. with density (1.2g/ml) × 1000ml/L

This gives 1200 gm of solution..

4 M means 4 moles of NaOH per 1 lt. of solution

Now, Convert 4 moles to grams...

         Molar mass of NaOH = 23+16+1 = 40

         4 moles × 40 amu = 160 gm of NaOH..

1200 gm of solution - 160 gm of solute = 1040 gm of solvent..

Molality = 4 moles of solute ÷ 1.040 of solvent

         m = 3.84 molal NaOH..

I hope u understood..