Ch3 and Ch21 Objectives
Ch3
 Recall a very brief history of Atomic Theory ( Democritus, Dalton, Thomson, Rutherford)
 Know and understand the five main aspects of Dalton's Atomic Theory
 Know how Modern Atomic Theory is the same and different from Dalton’s Atomic Theory
 Recall some of the experiments that led to the identification of sub-atomic particles
(Cathode Ray Tube, Oil Drop, Gold Foil)
 Know the three particles that make up the atom and their relative charges, masses and
positions in the atom
 Be able to use the Atomic # and Mass # of an isotope to calculate the numbers of protons,
neutrons and electrons
 Know what the term isotope means
 Be able to perform calculations of weighted average atomic mass from isotope data
Ch21
 Be able to use neutron:proton ratio to make predictions about stability(belt of stability)
 Understand the phenomenon of radioactivity and the properties of radioactive particles
 Know the three most common forms of radioactive decay (alpha, beta, and gamma) and know
how the nucleus changes in each type of decay.
 Know protons and neutrons have substructures and consist of particles called quarks.
 Be able to write nuclear equations
 Understand the term mass deficit
 Know protons and neutrons in the nucleus are held together by nuclear forces that overcome
the electromagnetic repulsion between the protons.
 Understand the concept of half-life and be able to perform calculations related to it
 Know how to calculate the amount of a radioactive substance remaining after an integral
number of half lives have passed.
 Recall some uses of radioactivity
 Know alpha, beta, and gamma radiation produce different amounts and kinds of damage in
matter and have different penetrations.
 Know the energy release per gram of material is much larger in nuclear fusion or fission
reactions than in chemical reactions. The change in mass (calculated by E=mc2) is small but
significant in nuclear reactions.
 Understand the terms nuclear fission and fusion
 Understand, that in very general terms, radioactivity involves the rearrangement of the
nucleus and chemical reactions involve the rearrangement of electrons
 Know some naturally occurring isotopes of elements are radioactive, as are isotopes formed
in nuclear reactions.
 Know that how man-made elements are created.