Written by London Swaminathan


swami_48@yahoo.com



Date: 15 December 2018


GMT Time uploaded in London – 13-42

Post No. 5784

Pictures shown here are taken from various sources including google, Wikipedia, Facebook friends and newspapers. This is a non- commercial blog.

The story of the discovery of two elements is very interesting. America kept it as a top secret, but it was announced in a ‘Kids Quiz Radio Show’ in 1945!
The discoverers of americium chose an unusual way to announce their discovery in a children’s radio show in USA called Quiz Kids, broadcast on 11 November 1945.

The guest scientist on the panel that week was a 33 year old chemist, Glen T Seaborg, who had worked on the top secret atomic weapons programme that had produced two new elements, curium and americium. Americium came to light as part of the Allied project to develop nuclear weapons, so its discovery was kept secret until the end of Second World War. Its existence was officially announced a few days after the broadcast, and the following year Seaborg proposed naming it americium, after the continent on which it was first produced.

Americium is named after America. It is a radioactive, silvery metal.
Americium was first made in 1944 at the University of Chicago by a team which included Glen T Seaborg, Ralph A James, Leon. O Morgan and Albert Ghiorso. It was produced as a result of the bombardment of plutonium with neutrons in a nuclear reactor. It was in fact discovered after curium, the element which follows it in the Periodic Table.

Smoke Detector
It is widely used in smoke detectors. A smoke detector contains 150 micro grams of americium oxide. The price of americium oxide per gram was $1500 in the year 2000. 5000 detectors can be made in one gram.

Americium 243 is produced from plutonium 239 with a half -life of 7370 years. Americium 241 is used in smoke detectors. It is extracted from nuclear reactors.

Americium probably does occur naturally on earth, but only in incredibly tiny amounts in uranium minerals where nuclear fission may occasionally produce an atom.

Chemical Element

Chemical symbol –Am
Atomic number– 95
Melting point– 994 degree C

Curium for Pace makers

Curium 242 is produced in nuclear reactors by bombarding plutonium with neutrons. This isotope is used as power source for pacemakers and navigational buoys, and on space missions because it gives off 3 watts of heat energy per gram of metal. Its radiation can easily be shielded against.


Nuclear weapon tests from 1945 have pumped some curium into atmosphere.
Curium is a synthetic, radioactive metal belonging to the actinide group. It is silver in colour. Altogether there are 14 known isotopes. The ones made in kilogram quantities are curium 242 ( half- life 163 days) and curium 244 ( half- life 18 years). The longest lived isotope is curium 247, with a half-life of 16 million years.

Chemical properties

Chemical symbol Cm
Atomic number 96
Melting point 1340 degree C

The production of curium in large quantities in nuclear reactors solves a big problem. This helps to reduce the stockpile of plutonium which may be otherwise used for making nuclear weapons. Curium is relatively short lived and useful.

—- Subham—-