Formula & Definitions

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

Normality (N) = Molarity (M) × Equivalents (n)

Equivalents (n): The number of reactive units per molecule (e.g., H⁺ for acids, OH⁻ for bases). H₂SO₄ has n=2, HCl has n=1, H₃PO₄ can have n=1, 2, or 3 depending on the reaction, but typically n=3 is used for stock calculations.

Stock Molarity Calculation:

M_stock = (Weight % × Density [g/mL] × 1000 [mL/L]) / Molecular Weight [g/mol]

Dilution Calculation (using Molarity): M₁V₁ = M₂V₂

Where M₁ is the stock molarity, V₁ is the volume of stock needed, M₂ is the target molarity, and V₂ is the target volume.

If Normality is used, the calculator first converts the target Normality (N₂) to the target Molarity (M₂) using M₂ = N₂ / n, then performs the M₁V₁ = M₂V₂ calculation.