Molecular Weight

Molecular weight, abbreviated as MW, also called molecular mass, refers to the average mass of one molecule of a substance, 1⁄12 (0.083) the mass of carbon 12 atom.

 

Molecular weight formula

\(\large{ MW = \frac{ R^* }{ R   } }\)

Where:

Units	English	Metric
\(\large{ MW }\) = molecular weight	\(\large{\frac{lbm}{lbmol}}\)	\(\large{\frac{kg}{kmol}}\)
\(\large{ R }\) = specific gas constant	\(\large{\frac{ft-lbf}{lbm-R}}\)	\(\large{\frac{J}{kg-K}}\)
\(\large{ R^* }\) = universal gas constant	\(\large{ \frac{lbf-ft}{lbmol-R} }\)	\(\large{ \frac{J}{kmol-K} }\)