How to Calculate Molar Mass (Molecular Weight)

Finding molar mass (also called molecular weight, molecular mass, and gram formula mass) is an essential skill in chemistry. All my content organized at Breslyn.org (and get all my free chem video guides)!

There are three steps to finding the molar mass for a compound:

Steps 1 – Find the atomic mass of each element.
Step 2 – Multiple the atomic mass of each element by its subscript. No subscript means it is “1”.
Step 3 – Add up all masses and add units (grams/mole or g/mol).
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Supporting videos (complete explanations):
HCl: youtu.be/tDVYav28GaA
O2: youtu.be/W2ePrieqiDU
Ca(NO3)2: youtu.be/W89M6c9Tu68
Al2(SO4)3: youtu.be/m75CUhLXCIU
MgSO4 - 7H2O: youtu.be/6b6GadB28o4
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A few things to consider when finding the molar mass for:

- make sure you have the correct chemical formula.
- always include the units for molecular weight (grams/mole).
- make sure you do the math right - follow the order of operations.

Get more chemistry help at thegeoexchange.org/chemistry

Being able to find the molar mass for a compound is extremely important , especially for mole to gram conversions.