Molecular weight of organic substances

The Molecular Weight of Organic Substances Chart shows how a molecular formula becomes a number chemists can measure and use. By adding the atomic masses of every chemical element in a molecule—such as carbon, hydrogen, oxygen, and nitrogen—scientists determine its molecular weight and the closely related molar mass, usually expressed in grams per mole. Ethanol, for example, has the formula C₂H₆O and a molar mass of about 46.07 g/mol.

Chemists, laboratory analysts, pharmacists, and materials scientists use molecular-weight data to calculate precise quantities of chemical substances, prepare solutions, analyse unknown samples, and determine how much material a reaction requires. It connects atoms too small to see with substances that can be weighed on a laboratory balance. Yet molecular weight does not reveal everything: two compounds may contain the same atoms and have the same mass, while their different molecular structures give them remarkably different properties.

The Chemistry mobile app includes the Molecular Weight of Organic Substances Chart, giving you fast access to the same essential data used in chemical calculations and laboratory work. Download the application and use the table to explore how chemical elements, molecular formulas, moles, and measurable amounts fit together.