2.2 Relative mass

• Relative masses are measured against the relative mass of carbon-12
• Relative isotopic mass is the mass of an atom of an isotope compared with 1/12th of the mass of carbon-12
• Relative atomic mass takes into account the isotopes present in a sample of an element and the relative abundances of the isotopes
• Relative atomic mass is the weighted mean mass of an atom of an element compared with 1/12th of the mass of carbon-12
• Mass spectrometry is used to identify the elements in a sample and to determine the relative abundance of each element
• Molecular formula are used for simple molecular compounds
• Relative formula mass is used for giant compounds