It is necessary to understand these states of matter in order to understand what is happening, on a molecular level, when solutions are formed. Recall that solutions are also known as homogeneous mixtures . There are many ways to express the concentration of a solution. Probably the most common method of indicating the concentration of a solution of a solid in a liquid is molarity , which is the number of moles of solute divided by the volume of the solution, and was already discussed in chapter 4 . Thus, the molarity of a solution changes with temperature.
Mass percentage has no units.
If the solution consists of more than one solute, then the denominator is the sum of the moles of all components. Mole fraction has no units. Notice that since the molality of a solution is determined by the masses of solute and solvent, it is temperature independent. Do not use m as an abbreviation for moles. This only makes sense, or course, if the meaning of an equivalent is understood.