Molecular weight of c

C is the chemical symbol for carbon. Its commonly used standard atomic-weight value is about 12.01. The corresponding molar mass used in many introductory calculations is about 12.01 grams per mole of carbon atoms.

Meaning and context

An isolated carbon atom is not a carbon molecule, so atomic mass is usually the clearer term. A carbon-containing molecule has a molar mass determined by all atoms in its formula, not only the carbon contribution.

Examples and usage

For CO₂, one carbon contributes about 12.01 g/mol and two oxygens contribute about 32.00 g/mol. The total is about 44.01 g/mol. The C symbol by itself does not stand for that whole molecule.

What to check

Carbon isotopes have different masses, and a specific isotope such as carbon-12 is not the same as an average for a natural sample. Match the value and precision to the problem’s periodic table and distinguish grams from grams per mole.

Explore more: Chemistry and Elements