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.