Molarity Calculator

This calculator determines the mass, concentration, volume, or formula weight required to prepare a solution. Enter any three values, and the fourth will be automatically calculated.

How to calculate mass

Mass (g) = Concentration (mol/L) × Volume (L) × Formula Weight (g/mol)

What is mass?

Mass (m) represents the amount of matter in a substance. It remains constant and does not change with gravity, unlike weight, which is influenced by gravitational forces.

What is formula weight?

Formula weight (F.W.) is the total of the atomic weights of all atoms in a compound's empirical formula. For instance, sodium chloride (NaCl) consists of one sodium (Na) atom and one chlorine (Cl) atom. Sodium has an atomic weight of 22.99 g/mol, while chlorine's atomic weight is 35.45 g/mol. Thus, the formula weight of NaCl is 58.44 g/mol (22.99 g/mol + 35.45 g/mol).

What is final volume?

Final volume refers to the total volume of solution after all solutes have been dissolved. It is typically measured in liters (L), milliliters (mL), or microliters (µL). The final volume is a key factor in determining the concentration of the solution, as molarity is expressed in terms of the amount of solute per unit volume of solution.

What is molar concentration?

Molar concentration, also called molarity, measures the amount of solute in a given volume of solution, typically expressed in mol/L, mol/dm³, or mol/m³. It is denoted by M, for molar. To prepare 1 liter of a 0.5 M sodium chloride solution, you would use 29.22 grams of sodium chloride (0.5 mol/L × 1 L × 58.44 g/mol = 29.22 g).