3. mole fraction = the ratio of moles of one substance to the total moles of all substances in the solution.
 
Mole fraction is a dimensionless quantity, like a ratio. The sum of the mole fractions of all the components in a solution must equal to ONE.

In a solution containing n_A moles of solute and n_B moles of solvent, the mole fraction of solute, X_A, and the mole fraction of the solvent, X_B, can be expressed as follows:

X_A = n_A / n_A + n_B     X_B = n_B / n_A + n_B

4. mass percent = the percent of a solution's total mass that is solute.
 
Many commercial solutions are labeled with mass percent. This solution concentration compares the mass of the solute to the total mass of the solution.

For example, a 10% salt solution contains 10 grams of salt in each 100 grams of solution.

 

More Concentration Calculations

 
Supersaturated Solution