Nuclear and
Radiochemistry
Objectives
Defines radioactivity
Looks at the properties of nuclear radiation
Gives examples of calculations involving radionuclides and isotopic half-lifes
Discusses the uses of radioisotopes
The radioactivity of naturally occurring and artificially produced isotopes, nuclear
fission (the reactions involved in commercial nuclear reactors) and nuclear fusion
(the source of the sun’s power) are all examples of nuclear reactions (Fig. 21.1).
Radioactivity started as a scientific curiosity. From these humble beginnings devel-
oped nuclear power (the main provider of power for the generation of electricity in
some countries) and the awesome power of nuclear warheads.
Radioactivity
Radioactivity was discovered accidentally in 1896, when Antoine Henri Becquerel
(1852–1908) noticed that an uranium ore caused a photographic plate to blacken.
The uranium gave off invisible ‘rays’ which were similar to the X-rays discovered the
previous year. Forty-nine years later, doctors in Hiroshima reported that previously
unexposed X-ray plates in hospital vaults had been fogged by the radiation emitted
by the first atomic bomb.
Pioneering work in radioactivity was carried out by the husband and wife team of
Pierre and Marie Curie, who (in 1898) extracted the elements polonium and radium
from an ore called pitchblende. The harmful effects of nuclear radiation were then un-
known, and even today their laboratory notebooks remain dangerously radioactive.
21.1
Contents
21.1Radioactivity 39921.2Radionuclides and
radioisotopes 40121.3More about nuclear
radiation 40221.4Mathematics of
radioactive decay 40321.5Uses of
radionuclides 40521.5Revision questions 410Fig. 21.1The main types of nuclear reaction.
Nuclear fusionsNuclear reactions Nuclear Fissions
Radioactive decay21
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