A solution is prepared that is 23.44 wt% NaCl in water. What is the molality of the solution? explain the answer to me

Expert Answers
jeew-m eNotes educator| Certified Educator

Molality is the ratio between amount of substance of solute in moles and amount of solvent in kg.

Molality (M) = (moles of solute)/(mass of solvent)


Here the solute is NaCl and solvent is water.

23.44% wt means we have 23.44g of NaCl in 100ml of water.

For 1000ml of water we have `23.44xx10 = 234.4` g of NaCl.


Molic weight of NaCl = 58.44g/mol


moles of NaCl `= 234.4/58.44 = 4.01` moles


So we have 4.01 moles of NaCl in 1000ml of water.

Usually 1ml of water has a weight of 1g.

So in the solution we have 1000g = 1kg of water.


Molality = 4.01/1 = 4.01mol/kg


The molality of the NaCl solution is 4.01mol/kg