Frequently asked questions about molarity
What does molarity mean?
Molarity, or molar concentration, tells you how many moles of solute are present in one liter of solution. It is usually written as mol/L or simply M.
What formula is used to calculate molarity?
This calculator uses the formula M = m / (MW × V), where m is the mass of solute, MW is the molecular weight, and V is the solution volume. The same relationship can be rearranged to solve for any other missing value.
Can I calculate the mass needed for a target concentration?
Yes. Enter the molecular weight, solution volume, and target concentration, and the calculator will solve for the required solute mass. This is a common task when preparing lab solutions and buffers.
What is the difference between molarity and molality?
Molarity is based on liters of solution, while molality is based on kilograms of solvent. For most routine solution preparation and lab concentration work, molarity is the unit used most often.
Which units does the calculator support?
You can use common mass, volume, and concentration units, including M, mM, and uM. The calculator also shows mass concentration, which helps when you need to compare molarity with concentration values written in mass-per-volume form.
