Curium, it’s in the Mars Rover, it’s radioactive so don’t get it all over,
silvery-white and hard and brittle, named after the Curies, who worked far more than little.

 

Curium
Radioactivity
The Curies
The Cyclotron
Transuranium Elements
Uses of Curium
  Links  

 

 

Curium

Curium is element number 96 on the periodic table of elements. It is a transuranium element, which means it follows Uranium on the periodic table. It is also a member of the actinide group. Curium is a silvery-white metal that is hard and brittle. It has a high melting point of 1,340 degrees Celsius or 2,444 degrees Fahrenheit. Curium is an element not found naturally in nature, which means that it was created by scientists. To be exact, it was created by Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso at the UC Berkley in a cyclotron. It is named after the famous Curies, Marie and Pierre who won the Nobel Prize awards in 1903 and in 1911(Marie Curie only). It was created by bombarding a Plutonium with helium ions or, alpha particles.


Radioactivity

Radioactivity, or radioactive decay, is when atoms of one element, gives off enough energy to change into another atom. For example, carbon-14 turns into nitrogen-14 when it gives off radiation. When an atom will decay is completely random, but if scientists have enough atoms the decay rate is predictable.
The three major types of radiation in radioactive decay are: alpha particles, beta particles, and gamma rays. Alpha particles are the weakest and can be stopped by a sheet of paper. Beta particles are stronger and require a sheet of aluminum to be stopped. Gamma rays are the strongest of the three and require a very solid barrier to stop, such as a thick block of lead.

The Curies

Marie and Pierre Curie were a scientist couple who worked with radioactive elements. They met in France in 1894 while studying magnetic properties of metals. They would be married a year later.
However, the Curies are most famous for their work on radioactive elements, not magnetism. It was Henry Bequerel who inspired them to begin work on radioactivity. Their most famous accomplishment was the discovery of two new radioactive elements, polonium and radium. This granted them the Nobel Prize in Physics in 1903. They did this while studying Uranium. They realized that a sample of pitchblende (U3O8), an ore in which Uranium is most commonly found, was giving off lots of radioactivity, too much. All this radioactivity could not just be coming from the uranium in the sample. There must have been another source. The Curies searched for it and came out with not one, but two different sources. These would turn out to be Polonium, named for Poland, Marie’s homeland, and Radium, both of which gave off much more radiation than Uranium.

Cyclotron

Cyclotrons are particle accelerators. The first one was created by Ernest Lawrence in 1929 in Berkley. Cyclotrons work by placing the particle between two electrodes shaped like D’s. Logically, they are called “dees”. These dees can switched to repel or attract the particle. The particle is attracted into the dee, then at a specific time, the electricity is switched to repel the particle, giving it a curved path. The particle can only accelerate when it is in the gap between the two dees. Eventually the particle picks up more and more speed, until it is fast enough, and is launched at whatever atom it is to collide with. In the case of Curium, an alpha particle was in the cyclotron, and it was launched at plutonium.

Transuranium Elements

Transuranium elements are all elements that follow Uranium, number 92 on the periodic table. All are discovered artificially, and excluding plutonium and neptunium, none are found naturally on Earth. All of the transuranium elements are radioactive. The heavier the transuranium elements get, the more expensive they are to produce, as well as the difficulty to produce them. Beyond californium, elements have no major commercial use. It is just to expensive and/or difficult to produce them to be worth it. Curium was the third transuranium element to be synthesized. The first two were Neptunium and Americium.

Uses of Curium

Curium has no major commercial uses in the world. It is not produced in large amounts. Out of all isotopes though, Curium-242 and Curium-244 have been produced in larger multigram amounts. Curium-242 gives of an impressive 120 watts but has a short half-life which doesn’t make it very practical. However, Curium-244, an isotope, was used power the Alpha particle X-ray spectrometer on the Mars Exploration Rover. Other possible uses for curium may be in pacemakers, because of its high wattage in small amounts, and in ocean buoys, where longer lasting isotopes can be used so that they will not have to be replaced as often.

 

Basic Facts of Curium-All You Need to Know
Number of Isotopes Twenty Isotopes
Longest Half-Life 15.6 Million Years
Element Group Actinides
Boiling Point

3110 Degrees Celcius
Atomic #
Number 96
State of Matter Solid

 

Glossary  
Transuranium Elements following Uranium on the Periodic Table
Radioactiove Decay When atoms lose particles of energy, and change elements
Cyclotron A type of particle accelerator which uses magnets to move the particle.
Half-life The time takes for half the atoms in a sample of an element to decay (change into a diferent element)
Isotope

An atom of an element that has the same number of protons but a different number of neutrons
Synthesized Artificially created

 

Links

Curium is a trans-uranium element. To find out more about Uranium click here. It is also named after the Curies, who are credited with the discovery of two other elements, Polonium, and Radium.

 

 

Bibliography


"Curium." Los Alamos National Lab. 15 Dec. 2003. University of California. 6 Feb. 2009 <http://periodic.lanl.gov/elements/96.html>.

"Curium." World Book Encyclopedia. Chicago, Illinois: World Book, 2006.

Frank, David V., Beth Miaoulis, T. Griffith Jones, Steve Miller, John G. Little, and Jay M. Pasachoff. Focus on California Physical Science. Boston, Massachusetts: Pearson Prentice Hall, 2008.

Gagnon, Steve. "Curium." Jefferson Lab. 6 Feb. 2009 <http://education.jlab.org/itselemental/ele096.html>.

Jackson, Tom. Radioactive Elements. Tarrytown, New York: Marshall Cavendish Inc, 2005.

Stwertka, Albert. A Guide To The Elements. New York, New York: Oxford UP, 2002.



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