What is the formula for calculating molarity?

Molarity, which is a measure of concentration, is defined as the number of moles of solute present in one liter of solution. The formula for molarity serves to relate the amount of substance (in moles) to the volume of the solution (in liters). Specifically, it quantitatively expresses how much solute is dissolved in a given volume of solvent.

By using the formula M = moles of solute / liters of solution, one can determine the concentration of a solution accurately. This calculation is essential in various areas of chemistry, such as solution preparation, stoichiometric calculations, and titrations.

The other options lose sight of this relationship. For instance, calculating liters of solution per mole of solute or taking the product or sum of moles and liters does not provide a coherent or standard way to express concentration. Thus, utilizing the ratio of moles of solute to liters of solution is the correct approach to compute molarity.