Recall that molarity (
Temperature cannot affect the physical amount of solute in a solution unless the solute undergoes a reaction when heated in that particular solvent. In that instance, one substance would become another and the molarity of the two substances would change.
If the solvent is volatile and can evaporate out of the reaction container when the temperature is raised, solvent will leave the solution and the molarity of the solution would increase.
However, both of these instances are typically not considered in GenChem courses and any experiments that you would do in the lab would most likely be designed in such a way to prevent this.