pr

Science Dictionary
Pr  
The symbol for praseodymium.
American Heritage
Science Dictionary
praseodymium   (prā'zē-ō-dĭm'ē-əm)  Pronunciation Key 
Symbol Pr
A soft, malleable, silvery metallic element of the lanthanide series that develops a green tarnish in air. It is used to add a yellow tint to glass and ceramics and to make the glass used in welding goggles. Atomic number 59; atomic weight 140.908; melting point 935°C; boiling point 3,127°C; specific gravity 6.8; valence 3, 4. See Periodic Table.
The American Heritage® Science Dictionary
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