Determine the solution volume in liters (L)
Determine the amount of solute in moles (mol)
Use the formula: Molarity (M) = moles of solute / liters of solution
If given mass (g): convert to moles using moles = mass / molar mass
If given concentration in another unit (e.g., g/L): convert to molarity using M = (g/L) / (molar mass)
If preparing a dilution: use M1V1 = M2V2
Check units: moles in mol and volume in L to get molarity in mol/L