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The ChemCollective >> Stoichiometry Tutorials>> Molecular Weight

Stoichiometry Tutorials: Part 4 - Calculating Molecular Weight / Molar Mass (from a complete OLI stoichiometry course)

The molecular weight is the mass of one mole of a substance. Usually, the units used for this are grams per mole. In this movie, we show how to calculate the molecular weight of a substance from the atomic weights given on the periodic table. On another page, we use the molecular weight to convert between the macroscopic scale (grams of a substance) and the microscopic scale (number of molecules of that substance).

Text version of this movie.

Element Atomic Weight (g/mol)
Ba 137.327
C 12.0107
Ca 40.078
Cr 51.9961
H 1.00794
Mg 24.3050
N 14.0067
Na 22.989770
O 15.9994
P 30.973761

Use the data from the periodic table shown above to answer the following questions.

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   Page Last Updated: 02.15.2011