[Free Registration/Login may be required to access all resource tools.] Students explain the workings of a mass spectrometer, and describe how this device is used to determine average atomic mass.

Tutorial explains isotopes, atomic weight and how isotopes can be detected using mass spectrometry. Examples are given.

This site provides an overview of elements and atoms, the building blocks of matter.

In this online biology textbook, learn about atoms and molecules as they relate to life. Find out about topics such as electrons and energy, chemical bonding, and chemical reactions.