What is the definition of molarity in a solution?

Molarity is defined as the number of moles of solute present in one liter of solution. This definition highlights the relationship between the amount of solute (expressed in moles) and the volume of the entire solution (expressed in liters).

Molarity is a crucial concept in chemistry because it allows chemists to quantify concentrations of solutions accurately and is heavily used in stoichiometry for reactions in solutions. The formula for calculating molarity is given by:

Molarity (M) = moles of solute / liters of solution

This means that if you have a solution and you want to calculate its molarity, you would need to measure the moles of solute you have dissolved and the total volume of the solution. Other definitions provided in the choices relate to different concepts, such as mass per volume or the amount of solute compared to solvent, which do not take into account the total volume of the solution. These distinctions are important in the context of solution chemistry.