You wish to prepare an IV solution, NaCl, with a mole fraction of 2.90*10-4.  a) how many grams of NaCl will you have to combine with 1 L of water to make the solution? b) what is the molality of the solution? c) what is the concentration in ppm?

Molality: It is the property of solution and it tells us about the number of moles of solute per kilogram of solvent. The unit of morality is mol/kg.

                                                          $molality=\frac{moles of solute}{kg os solvent}$

Mole fraction: It is the ratio of the number of molecules of a constituent N_i divided by the total number of all molecules N_tot.

_{$xi = \frac{Ni}{Ntotal}$}