Where do I find a compound's molar mass?

Add up the atomic masses of every atom in the compound's formula using a periodic table, or look up the compound directly.

Mass-to-Moles Calculator

Convert between mass and moles of a substance given its molar mass, a core calculation in stoichiometry.

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Formula

moles = mass (g) / molar mass (g/mol)

Converting Mass to Moles, and pH to pOH

How the mass-to-moles conversion and the pH-pOH relationship both work, with real chemistry examples.

Molarity Calculator

Calculate the molarity of a solution from moles of solute and volume.

Percent Yield Calculator

Calculate the percent yield of a chemical reaction.

Dilution Calculator (C1V1=C2V2)

Calculate the volume needed to dilute a stock solution to a target concentration.

Ideal Gas Law Calculator

Calculate pressure, volume, moles, or temperature using PV = nRT.

Boyle's Law Calculator

Calculate the new pressure or volume of a gas at constant temperature.

pH to pOH Calculator

Convert between pH and pOH for aqueous solutions at 25°C.