Question

100 mL of a solution of compound “X” has the following properties:

–Molarity: 2M –MW of “X”: 500g/mole

–Density of compound “X”: 5.0g/cm3

What dilution factor would be required to make a solution of 1% (v/v) of “X”?

Answer 1

Molarity(M)= w/mwt*1000/V

                  

Mwt = molarmass of X = 500g/mole

V/v% = 1%

d= density of solute = 5 g/cc

Molarity(M) of diluted solution =   v/v%*d*10/mwt

                                                          = 1*5*10/500

                                                           = 0.1 M

from dilution law ,

let us consider volume of dilute solution (V2) =100 ml

M1V1 = M2V2

M1 = molarity of standard solution = 2 M

V1 = volume of standard solution take = ?

M2 = Molarity of diluted solution = 0.1

V2 = volume of diluted solution = 100 ml

2*V1 = 0.1*100

V1 = 5 ml

so that ,

dilution factor = Vfinal / Vinitial =100/5= 20