Terbium (Tb)

Atomic Number: 65

Relative Atomic Mass: 158.92535

Electronegativity: 1.10

Atomic Radius (Picometers): 175

Appearance: Silver-White

Occurrence: Natural

Melting Point (Kelvin): 1629

Boiling Point (Kelvin): 3503

Stable Isotopes: 159

Discoverer: Carl Mosander  in 1842

Properties: Ductile, Malleable, Soft

First Use: Unknown

Modern Uses: Fluorescent Lamps, Alloys

Picture Courtesy of images-of-elements.com

©2011 Grant Dwyer

Gadolinium (Gd)

Atomic Number: 64

Relative Atomic Mass: 157.25

Electronegativity: 1.20

Atomic Radius (Picometers): 180

Appearance: Silver-White

Occurrence: Natural

Melting Point (Kelvin): 1585

Boiling Point (Kelvin): 3546

Stable Isotopes: 154, 155, 156, 157, 158

Discoverer: Jean Charles Galissard de Marignac in 1880

Properties: Ductile, Malleable

First Use: Unknown

Modern Uses: Compact Discs, Alloys

Picture Courtesy of images-of-elements.com

©2011 Grant Dwyer

Europium (Eu)

Atomic Number: 63

Relative Atomic Mass: 151.964

Electronegativity: 1.20

Atomic Radius (Picometers): 185

Appearance: Silver-White

Occurrence: Natural

Melting Point (Kelvin): 1099

Boiling Point (Kelvin): 1802

Stable Isotopes: 153

Discoverer: Eugene-Anatole Dermarcay in 1896

Properties: Hard, Ductile

First Use: Television Sets (Unknown)

Modern Uses: Fluorescent Lamps, Superconducting

Picture Courtesy of Jurii

©2011 Grant Dwyer

Samarium (Sm)

Atomic Number: 62

Relative Atomic Mass: 150.36

Electronegativity: 1.17

Atomic Radius (Picometers): 185

Appearance: Silver-White

Occurrence: Natural

Melting Point (Kelvin): 1345

Boiling Point (Kelvin): 2067

Stable Isotopes: 144, 149, 150, 152, 154

Discoverer: Paul Emile Lecoq de Boisbaudran in 1879

Properties: Hard

First Use: Control Rods (Unknown)

Modern Uses: Magnets, Chemical Reagent

Picture Courtesy of images-of-elements.com

©2011 Grant Dwyer

Promethium (Pm)

Atomic Number: 61

Relative Atomic Mass: About 145

Electronegativity: 1.13

Atomic Radius (Picometers): 185

Appearance: Metallic

Occurrence: Decay

Melting Point (Kelvin): 1315

Boiling Point (Kelvin): 3273

Stable Isotopes: None

Discoverers: Chien-Shiung Wu, Emilio Segre and Hans Bethe in 1942

Properties: Radioactive

First Use: Unknown

Modern Uses: Light Source, Atomic Battery

Picture Courtesy of images-of-elements.com

©2011 Grant Dwyer

Neodymium (Nd)

Atomic Number: 60

Relative Atomic Mass: 144.242

Electronegativity: 1.14

Atomic Radius (Picometers): 185

Appearance: Silver-White

Occurrence: Natural

Melting Point (Kelvin): 1297

Boiling Point (Kelvin): 3347

Stable Isotopes: 142, 143, 145, 146, 148

Discoverer: Carl Auer von Welsbach in 1885

Properties: Soft

First Use: Glass Dyes (1927)

Modern Uses: Magnets, Lasers

Picture Courtesy of images-of-elements.com

©2011 Grant Dwyer

Praseodymium (Pr)

Atomic Number: 59

Relative Atomic Mass: 140.90765

Electronegativity: 1.13

Atomic Radius (Picometers): 185

Appearance: Grey-White

Occurrence: Natural

Melting Point (Kelvin): 1208

Boiling Point (Kelvin): 3793

Stable Isotopes: 141

Discoverers: Carl Auer von Welsbach in 1885

Properties: Soft, Ductile, Malleable

First Use: Glass Colourisation (1920s)

Modern Uses: Aircraft Engines, Fire Starters

Picture Courtesy of Jurii

©2011 Grant Dwyer