Mass spectrometry and calculationsCobalt is a transition metal with the atomic number 27 and relative atomic mass of 58.93....To find cobalt's relative atomic mass ( any element's mass in fact) we use a mass spectrometer which vaporizes the atoms in a vacuum, at which ionization occurs; when the isotopic element is in mass spectrometer it has different mass peaks to which the mass spectrometer compares the peaks of the non isotopic element... a ratio of the peaks' heights is taken (for example 3 : 1) which determines the percentage of abundance, then taking the Ar of the isotopes we can determine what the relative atomic mass is through this calculation and we'll take the two stable isotopes of chlorine *while cobalt is the main example, its only naturally occurring isotope is Co-59, so we'll stick to using chlorine as an example* Cl-35 and Cl-37 to do this we multiply its abundance in percentage (converted from the ratio 3:1) add them, then divide by 100 *refer to calculations tab* ~ ((35*75)+(37*25)/100) will give us the relative atomic mass of chlorine 35.5.
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