Answer to Question #60750 in Physical Chemistry for Sanjukta Ghosh

Question

What is the molality of this solution?

A dilute soln is prepared by dissolving W2 g of a non-volatile and non-electrolyte solute (M.wt.=M2) in W1 g of a solvent (M.wt=M1). What is the concentration of solute in molality?

In W1 g of solvent, no.of moles of solute present is W2/M2 moles

In 1 g of solvent, no. of moles of solute present is W2/(M2 x W1) moles

In 1000g of solvent, no. of moles of solute present is W2 x 1000/ (M2 x W1) moles = say n

So, is Molality= no. of moles of solute/ 1000g of solvent

= n/1000 ?