Briefly describe the concept behind a TEM detector. (2.4)
What will be an ideal response?
Answer: Most of the size of an atom consists of the cloud of electrons that orbit the nucleus. If many electrons exist in a small area around the nucleus, then there is a good chance that electrons fired in the TEM will collide with an orbiting electron and bounce off it, rather than continuing through to the detector. If, however, the electrons are widely spaced around a nucleus, then the fired electrons may pass through the atom without hitting any obstacles. This means that the shadows in the TEM image may not represent all of the types of atoms in a mineral, but rather only the atoms with closely clustered electrons.
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Indicate whether the statement is true or false