Radium

Andrew Muckin and Chantel Zionkowski

Radioactive
 * Atomic Number:** 88
 * Atomic Weight:** 226
 * Melting Point:** 973 K (700°C or 1292°F)
 * Boiling Point:** 1413 K (1140°C or 2084°F)
 * Density:** 5 grams per cubic centimeter
 * Isotopes:** 26
 * Phase at Room Temperature:** Solid
 * Element Classification:** Metal
 * Period Number:** 7 **Group Number:** 2 **Group Name:** Alkaline Earth Metal
 * Color:** Its appearance is almost pure white, but it readily oxidizes on exposure to air, turning black
 * Texture:** None

Radium's most stable isotope, radium-226, has a half-life of about 1600 years. It decays into radon-222 through alpha decay or into lead-212 by ejecting a carbon-14 nucleus..
 * __Discovery:__** Radium was discovered by Marie Sklodowska Curie, a Polish chemist, and Pierre Curie, a French chemist, in 1898. Marie Curie obtained radium from pitchblende, a material that contains uranium, after noticing that unrefined pitchblende was more radioactive than the uranium that was separated from it. She reasoned that pitchblende must contain at least one other radioactive element. Curie needed to refine several tons of pitchblende in order to obtain tiny amounts of radium and polonium, another radioactive element discovered by Curie. One ton of uranium ore contains only about 0.14 grams of radium. Today, radium can be obtained as a byproduct of refining uranium and is usually sold as radium chloride (RaCl2) or radium bromide (RaBr2) and not as a pure material.

When mixed with beryllium it is a neutron source for physics experiments.
 * __Uses:__** Radium had been used to make self-luminous paints for watches, aircraft instrument dials and other instrumentation, but has largely been replaced by cobalt-60, a less dangerous radioactive source. A mixture of radium and beryllium will emit neutrons and is used as a neutron source. Radium is used to produce radon, a radioactive gas used to treat some types of cancer. A single gram of radium-226 will produce 0.000l milliliters of radon a day..
 * __Reactions with humans:__** During the 1930s it was found that workers' exposure to radium by handling luminescent paints caused serious health effects which included sores, anemia and bone cancer.

__**Biological role:**__ Radium has no biological role.


 * __Health Hazards:__** Radium is studied in a few nuclear research laboratories where its high radioactivity requires special handling techniques and precautions.


 * __Abundance of Element in Universe:__** Radium is found naturally in uranium ores such as pitchblende (mostly UO2). One tonne of pitchblende might yield about 0.15 g of radium. Ores containing radium are found in Zaire, Australia, Canada, and USA (New Mexico, Utah, and in small amounts in carnotite sands from Colorado). Recovery is costly. Some estimates suggest that every square kilometre of soil to a depth of a 40 cm contains about 1 g of radium.


 * __Important Element Compounds:__** Radium bromide, Radium Cloride


 * __How much radium can you buy for $100?__** The cost of radium is 10oz. for $100.

Isotopes of radium occurring within the radioactive disintegration chains of actinium and thorium were known as: > > > media type="custom" key="3059744" > > http://www.webelements.com/radium/ --Webpage http://player.discoveryeducation.com/index.cfm?guidAssetId=DC3E55F0-7607-45E9-A428-DADC69C2DEF3&blnFromSearch=1&productcode=US---Video
 * __Isostopes:__** Radium has no stable isotopes. A standard atomic mass cannot be given.
 * **__//actinium X//, 223Ra__**
 * **__//thorium X//, 224Ra__**
 * **__//mesothorium I//, 228Ra__**