Relative Atomic Mass
| Formula / Notation | Ar = m_atom / (1/12 × m_C-12) |
|---|---|
| Also Known As | Atomic weight, standard atomic weight, Ar, average atomic mass |
What is Relative Atomic Mass?
The relative atomic mass (Ar, also called atomic weight) is the ratio of the average mass of atoms of an element (taking into account the natural abundances of isotopes) to one-twelfth of the mass of a carbon-12 atom. It is a dimensionless quantity. The relative atomic mass is the weighted average of all naturally occurring isotopes of the element.
Formula & Notation
Other Names / Synonyms: Atomic weight, standard atomic weight, Ar, average atomic mass
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
The relative atomic mass (Ar, also called atomic weight) is the ratio of the average mass of atoms of an element (taking into account the natural abundances of isotopes) to one-twelfth of the mass of a carbon-12 atom. It is a dimensionless quantity. The relative atomic mass is the weighted average of all naturally occurring isotopes of the element.
Calculating molar masses. Stoichiometric calculations. Preparing solutions of known concentration. Gravimetric analysis. Isotope dilution mass spectrometry. Atomic weight determination by mass spectrometry. Teaching fundamental chemistry.
Theoretical concept — no direct safety concerns.
The formula or notation for Relative Atomic Mass is: Ar = m_atom / (1/12 × m_C-12)