How to Calculate Molars

The value of a mole is approximately 6.02214078(18)---1023.

A mole is the molecular weight of a substance. It is a unit of measure that serves as a convenient way to standardize quantities of a substance. Specifically, a mole of a substance is equal to the sum of the atomic weight of the substance in grams. For example, one mole of carbon-12 has a mass of about 12 grams because its approximate atomic mass is 12 atomic mass units.

Things You'll Need

• Pen
• Paper
• Calculator
• Scale

Instructions

1. Measure the substance's mass in grams.

2. Find the tabulated atomic weight of the substance and multiply this amount by the molar mass constant, 1 gram per mole.

3. Divide the mass in grams by the molar mass expressed in grams per mole.

4. Cancel the units so that the final value is represented in moles.

Tips & Warnings

• Use a periodic table of elements to determine the substance's atomic weight.

• If your final value does not end up in molar units, check your calculations as there is likely to be an error.

References

• CliffNotes; The Mole Unit