Praseodymium Pr		By Jonathan Ms Eagle's 8th Grade Science Class Mill Valley Middle School Marin, CA
"If you don't want your grass looking lum, dye it with praseodymium."
History Praseodymium was discovered in 1885. Baron von Welsbach separated teh componets of didymium into neodymium and praseodymium. Baron von Welsbach obtained these from the mineral samarskite. These two elements are twins. Neodymium means the new twin. Praseodymium comes from the Greek words meaning "Prasios" meaning green and "didymos" meaning twin. It was called the green twin because of the green salts it gave off.
Uses Praseodymium is used in ceramics. Some people use it to make their lawns look really green. It makes grass look greener because of the many green salts it gives off. It is also used in welders masks to filter out the yellow light. It is used in many alloys. When mixed with it is used in searchlights.
Glossary Lanthanides- Isotopes-Atoms that have the same number of protons but have different numbers of neutrons Half Life- Valance Electron-Electrons that are in the outer most energy level.	Characteristics Praseodymium has 59 Electrons, 59 Protons and 82 Neutrons. Praseodymium has two valance electrons. Praseodymium's atomic number is 59 and its atomic mass is 140.9. Praseodymium is in Period 6 and it's in the Lanthanide group. Praseodymiums is a solid, and it's a metal. Praseodymiums' melting point is 935ºC or 1715ºF. Praseodymiums's boiling point is 3127ºC or 5660.6ºF. Its density at 293ºK is 6.77g/cm3. Praseodymium is a rare earth element. It color is silvery white.Praseodymium costs $170/100g when it's pure.
Atomic Structure Praseodymium has six energy levels. The first level has 2 electrons, the second has 8 electrons, the third has 18 electrons, the fourth has 21 electrons, the fifth has 8 electrons and the sixth has 2 electrons. It's crystal structure is hexagonogal. Its's Isotopes and Half Life's are: Pr-141:STABLE Pr-142:19.12 hours Pr-143:13.57 days Pr-144:17.28 minutes Pr-145:7.2 minutes	Bibliography Chemicool Periodic Table Enviromental Chemistry Periodic Table Interactive Periodic Table of the Elements Periodic Table Pictorial Periodiv Table Web Elements Periodic Table Images found at: Interactive Periodic Table of the Elements www.flamingtext.com