hafnium

Trang Mai project: All About The Elements Ms.Marx =Hafnium=

__Introduction__ : this is kind of a strange name to us :Hafnium which is in group 4 ( transition mental), period 6 in periodic table __Electron configuration:__
 * symbol: Hf
 * atomic number: 72
 * atomic mass: 178.49
 * in the most common isotope : Hafnium_178 with 51%,
 * the number of proton and electron :72
 * the number of neutron: 106

[Xe] 4f14 5d2 6s2 __Physical properties__: solid, bright gray- silvery color; easy to be drawn into thin wire or piece. __Chemical properties__: hafnium is not an active element, may react with hot acid __History__: Hafnium was discovered in 1923 by Dirk Coster and George Charles von Hevesey by using X- ray analysis __Uses__: Hafnium is used in nuclear control rod, which is used to control number of neutron in nuclear power production. ( thanks to its physical property: absorb neutron) __Common form__: __Stable isotopes__: there are 6 stable isotopes Hafnium that are all radioactive but have different number of neutron in nucleus so they have different numbers of neutron in nucleus. __Most common radioactive isotope__ : there are some radioactive isotopes of Hafnium that decay to another elements: [] [] [] [] [] [] [|http://webelements.com/hafnium/history.html] [|http://webelements.com/hafnium/isotopes.html] http://www.webelements.com/_media/elements/element-pics-theo/72_Hf_3.jpg
 * melting point: 2233º C
 * boiling point: 4603º C
 * density: 13.31g/ cm2
 * hafnium can absorb neutrons very easily
 * in high temperature condition, hafnium can react with Oxygen, Boron, Silicon, Sulfur, Carbon, Nitrogen
 * it is found in zircon.
 * Latin name :"Hafnia" which means Copenhagen.
 * it got its name from the name of the city it was found.
 * because it is very ductile, so it can be used to make combine material>> make mechanical product.
 * hafnium doesn't exist as an element, but in compounds : HfSiO4, HfO2, HfN ,HfB2 ,HfH2 ,HfCl4, Hf(CO)7, HfI3
 * HfSiO4 is found on the Earth's crust.
 * Hafnium_174 ( with 102 neutrons)
 * Hafnium_176 ( with 104 neutrons)
 * Hafnium_177 ( with 105 neutrons)
 * Hafnium_178 ( with 106 neutrons)
 * Hafnium_179 ( with 107 neutrons)
 * Hafnium_180 ( with 108 neutrons)
 * Hafnium_172 :decayed by electron capture decay to produce Lutetium_172
 * Hafnium_173: decayed by electron capture decay to produce Lutetium_173
 * Hafnium_175: decayed by electron capture decay to produce Lutetium_175
 * Hafnium_181: decayed by Beta decay to produce Tantalum_181
 * Hafnium_182: decayed by Beta decay to produce Tantalum_182