2. Actinium Type = Actinoid Symbol Atomic weight 227.0278 Atomic volume = 27.54 cm³/mol
3. Discovered by Anne Debierne in 1899. -Debierne worked with Marie Curie and discovered actinium in pitchblende (uranium ore) from which radium and polonium had already been extracted. He was able to identify the presence of a new element because the radioactive emissions profile of his sample could not be explained by the presence of any known element
4. State of Matter : Solid Melting Point: 1323.2 K (1050ºC) Boiling Point: 3471 K (3199ºC) Density at 293 K = 10.07 g/cm3 Structure = race-centered cubic Uses = neutron production Harmful effects: highly radio active Characteristics: radioactive, glows in the dark Color: Silvery white Abundance in Earth’s Crust: 0.0005 parts per trillion by weight
5. Origin of Name=Greek word “aktinos” meaning ray Type= Actinoid/Actinide Number of protons= 89 Number of electrons = 89 Number of neutrons = 138 (may vary) Most Common isotope = actinium-227 and actinium-228 Actinium-227, 138 neutrons Actinium-228, 139 neutrons
6. Reactions Reaction with air: mild, w/ht ->Ac2O3 Reaction with 15 MHNO3: mild ->Ac (N3O3) Reaction with 6M HCI: mild -> H2; AcCl3
7. Compounds Oxide = AC2O3 Hydride = AcH2 Chloride = AcCl3 Abundance = 0.0005 parts per trillion by weight
8. Occurrence in Nature Actinium is found in uranium ores. An ore is a mineral mined for the elements it contains. It is produced by the radioactive decay, or breakdown, of uranium and other unstable elements. Actinium can also be artificially produced. When radium is bombarded with neutrons, some of the neutrons become part of the nucleus. This increases the atomic weight and the instability of the radium atom. The unstable radium decays, gives off radiation, and changes to actinium. Actinium metal of 98 percent purity used for research purposes can be made by this process.
9. Actinium uses Actinium of 98 percent purity is prepared for research studies. Used for Thermoelectric power. Power is generated by Heat, powered by Actinium. Radium is 1,000,000 times more radioactive then plutonium. Actinium is 150 times more radioactive then Radium, therefore is a great source of energy
10. Naturally occurring Actinium is rare. It can be used as neutron source, alpha rays source for radio-therapy. Actinium is can be a crucial element to our society because it is originated from Uranium ores, and contains radioactive compounds. It is used as a source to create Thermoelectric power. It is highly radioactive.
11. Number of Energy Levels: 7 First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 32 Fifth Energy Level: 18 Sixth Energy Level: 9 Seventh Energy Level: 2
12. In Actinium’s lewis dot structure there are two valence electrons in the outer most level.
