Transcript chapter 24

Application of Nuclear Chemistry
 Cancer
Treatment – Cancer cells are
more susceptible to radiation bc they
are fast growing. Thyroid cancer can
be treated with Ir-192 or Co-60.
 Food Preservation – Strawberries are
exposed to Co-60. This kills most of
the bacteria and mold on the food.
 Radioisotope
– an isotope that is
radioactive.
 Half-life – The amount of time it
takes for ½ of a sample of a
radioactive isotope to decay. (1/2
of the radioactive atoms)
 Ex. 90Sr = 28.8 yrs
Radiocarbon Dating
 uses
carbon-14
 carbon-14 is radioactive
 half-life is 5730 yrs
 Produced naturally from reaction
between N-14 and cosmic rays
 Rate of production carbon-14 = rate
of decay of carbon-14
Nuclear Bombardment
Reactions
Process used to make stable nuclei
unstable by bombarding nucleus with a
stream of particles Usually neutrons
 Have to be fast because nucleus is
positive and particles are positive. Makes
this hard to do.
 Byproducts are electrons

Fission
A large nucleus is split into 2 smaller
nuclei or approximately equal mass.
 U-235 releases 3 neutrons.
 If this continues a chain reaction will
occur.

Measuring Radiation
 Dosimeter
– Measures the total
amount of radiation that a person has
received. A badge with a piece of film
is worn, if the film is developed, the
person has been exposed to radiation
Radiation
Alpha particles – weakest of all particles
Can be written as a helium nucleus
 Beta – medium strength can also be
written as an electron
 Gamma – strongest type of radiation.
Affects electrons in the body.

REM
Used to measure radiation exposure in
humans
 Includes BOTH the amount of energy
transferred by radiation AND the
sensitivity of the body to that type of
radiation.
 Leukemia – Most common type of cancer
caused by radiation.
