Page 26 - Curriculum Visions Dynamic Book

Other common radioactive elements
A whole series of radioactive elements has been discovered in the last century. Most of these do not occur naturally, or, if they do, exist for only very short periods of time.
In fact, many new elements can be made in the laboratory by bombarding an element with neutrons. This is done inside a nuclear reactor.
Plutonium
Plutonium, a silvery metal with a half-life of 24,000 years, was discovered in 1940 and named after the planet Pluto. It occurs in very tiny quantities in association with uranium. Large lumps of plutonium are warm to the touch due to the natural release of energy within the material. Most of the plutonium needed is made from uranium.
Plutonium is a vital fuel for nuclear reactors and nuclear bombs. It is used especially as a fuel in the types of reactor designed by France and Russia. A mass of just 5 kg of plutonium (about the size of a large orange) will make a nuclear bomb.
Plutonium has also been used successfully to make long- life batteries used in heart pacemakers and for powering long-distance spacecraft such as the Voyager series.
The radiation from a piece of plutonium is very readily shielded, for example, by rubber gloves. The major concern is from plutonium dust that might be inhaled. Plutonium
is chemically similar to calcium and therefore can replace it in bones, irradiating the nearby marrow cells and causing leukaemia.
 The fuel element from an advanced gas-cooled reactor. When filled
with fuel, one of these elements produces as much energy as about 3000 tonnes of coal.
 Handling radioactive materials in lead-lined chambers.
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