This document provides an introduction to nuclear chemistry concepts. It discusses radioactivity, nuclear reactions, radioactive emanations, and penetrating power of different types of radiation. It also covers identifying radioactive elements, natural and artificial transmutations such as fission and fusion, nuclear reactors, shielding, disposal of radioactive waste, and practical applications of radioactivity including uses as tracers in medicine and food preservation.

1. By R. Frank 2014
NUCLEAR CHEMISTRY
NYS REGENTS CHEMISTRY

2.  Radioactivity is the spontaneous disintegration of
the nucleus along with the emission of particles and
energy.
 Nuclear reactions differ from chemical reactions in
that the original atoms are changed into atoms of
another element. (Photo)
INTRODUCTION TO NUCLEAR CHEMISTRY

3.  Emanations are the particles released when an
element disintegrates.
EMANATIONS

4.  Penetration Power is the ability of radiation to pass through
matter.
 Gamma Particles have the most penetration power, and alpha
particles have the least penetration power.
PENETRATING POWER

5. On the reference tables, elements are
radioactive if the atomic masses are in
parentheses ( ). For example, elements with
an atomic number of over 83 have atomic
masses that are all in parentheses, and are
therefore radioactive.
IDENTIFYING RADIOACTIVE ELMENTS

6.  Transmutations when one element is changed to another by a
change in the nucleus. When an element forms an emanation
(Table O), it is a natural transmutation.
 An example of a natural transmutation is found below.
NATURAL TRANSMUTATIONS

7.  Artificial transmutations occur when a radioactive nuclei is hit
with high energy particles, producing neutrons. Examples are
fission and fusion.
 Fission occurs when heavy nuclei are split to (usually) produce
3 extra neutrons and a lighter nuclei.
(Remember, “Fission is Division”)
 Fission Reaction:
 Fusion occurs when two light nuclei fuse to form a heavier
nucleus. (2 small atoms form 1 larger atom)
 Fusion Reaction:
ARTIFICIAL TRANSMUTATIONS

8.  1. Which radioactive emanations have a charge of -1?
 2. Which emanation has the most penetrating power?
 3-4. Identify the reactions taking place in the photo below. Is
it fusion, fission, or a natural transmutation. Why?
 5. How does a nuclear reaction differ from a chemical
reaction?
 6. Is the element Actinium (Ac) a radioactive element? Why or
why not? Is Carbon (C) a radioactive element?
MID-UNIT COMPREHENSION CHECK

9.  Stability of an element is dependent on its
ratio of protons to neutrons. An element is
stable when this ratio is close to 1:1.
 A half-life is the time it takes for half the
atoms of a radioactive nuclide to decay. The
shorter the half-life, the less stable it is.
HALF-LIFE

10.  Fissionable fuels power the reactor and include U-233, U-235,
and Pu-239.
 Moderators decrease the speed of neutrons, and can be heavy
water, water, beryllium, or graphite.
 Control rods absorb extra neutrons, and can be baron or
cadmium.
 Coolants keep the temperature of the reactors cool. They
include water, heavy water, helium, carbon dioxide or molten
lithium and sodium
NUCLEAR REACTORS

11. NUCLEAR REACTORS
Fissionable FuelsFissionable Fuels
Control Rods
Coolants

12.  Shielding prevents radiation leakage.
 External – High-density concrete. (Shown)
 Internal – Steel.
SHIELDING

13.  Solid and liquid radioactive wastes are encased and stored
underground.
 Radioactive gases are stored until they can be safely released
into the environment.
DISPOSING OF RADIOACTIVE WASTE

14.  Tracers are radioactive isotopes used to follow the course of a
chemical reaction.
 IODINE-131 is used for thyroid disorders.
 CARBON-14 is used for carbon dating of organic materials,
living things, and photosynthetic reactions.
 URANIUM-238 and LEAD(Pb)-206 are used for geologic dating.
 TECHNICIUM (Tc) -99 is used for brain tumors.
 RADON-226 and COBALT-60 are used for cancer treatments
because they kill living cells.
RADIOACTIVE TRACERS

15.  Radiation is used to preserve food.
 Radiation is used in medicine because of its short half-life
and quick elimination.
PRACTICAL USES OF RADIOACTIVITY
R. Frank 2014