Atomic History and Structure
Test Objective
Chapter 5, sections 1-3 of text book
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Be able to define an atom and discuss how the atoms of one element are
different from another.
Be able to identify the defining characteristics of protons, neutrons, and
electrons and indicate their location in the atom.
Understand what particles are responsible for the mass of an atom.
Understand what particles are responsible for the charge of an ion.
Describe atoms, ions, and isotopes. (i.e. how are they alike, how are they
different?)
Distinguish between atomic number, mass number, and ionic charge, and
average atomic mass.
Be able to write the symbol of a nuclide (see pages 58-59 of notes)
Know when it is appropriate to use the units of grams for mass, or amu for
mass.
Know what amu stands for
Know how to calculate the average atomic mass of an element from mass and
isotopic abundance data.
While specific scientists and their accomplishments will not be asked directly
on the test, you should be able to identify how the electron was discovered
(see J.J. Thompson’s exp. with cathode rays tubes), the nucleus was
discovered (see Rutherford’s gold foil experiment), and how isotopes were
discovered (see J.J. Thompson’s exp. with Neon)