Spectrometry Measuring the Mass of Atoms and Molecules

Mass Spectrometry Measuring the Mass of Atoms and Molecules 

Atoms are converted to positively charged ions, accelerated, and passed through a magnetic field that deflects their path. The heaviest ions undergo the least deflection. 

A FIGURE 2.17 The Mass Spectrum of Chlorine The position of each peak on the A -axis indicates the mass of the isotope. The intensity (or height) of the peak indicates the relative abundance of the isotope. The intensity of the highest peak is usually set to 100% and the intensity of aU other peaks is reported relative to the most intense one. 

The mass spectrum of an elemental sample can be used to determine the atomic mass of that sample of the element. For example, consider the mass spectrum of a naturally occurring sample of silver. 

The two peaks correspond to the two naturally occurring isotopes of silver. We can determine the percent abundance of each isotope from the intensity of each line. However, the total intensity must be normalized—it must be made to equal 100%. We can accomplish this by dividing the intensity of each peak by the total intensity  

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