|
Actinium
|
Ac
|
89
|
Actinide
|
the Greek aktis, 'ray'
|
3
|
7
|
|
|
10.07
|
1323.00
|
3471.00
|
0.12
|
1.10
|
0.00
|
|
Cerium
|
Ce
|
58
|
Lanthanide
|
the then recently discovered asteroid Ceres, considered a planet at the time
|
|
6
|
140.12
|
0.00
|
6.77
|
1068.00
|
3716.00
|
0.19
|
1.12
|
66.50
|
|
Praseodymium
|
Pr
|
59
|
Lanthanide
|
the Greek praseios didymos meaning 'green twin'
|
|
6
|
140.91
|
0.00
|
6.77
|
1208.00
|
3793.00
|
0.19
|
1.13
|
9.20
|
|
Americium
|
Am
|
95
|
Actinide
|
The Americas, as the element was first synthesized on the continent, by analogy with europium
|
|
7
|
|
|
13.69
|
1449.00
|
2880.00
|
|
1.13
|
0.00
|
|
Promethium
|
Pm
|
61
|
Lanthanide
|
Prometheus of Greek mythology who stole fire from the Gods and gave it to humans
|
|
6
|
|
|
7.26
|
1315.00
|
3273.00
|
|
1.13
|
0.00
|
|
Neodymium
|
Nd
|
60
|
Lanthanide
|
the Greek neos didymos meaning 'new twin'
|
|
6
|
144.24
|
0.00
|
7.01
|
1297.00
|
3347.00
|
0.19
|
1.14
|
41.50
|
|
Samarium
|
Sm
|
62
|
Lanthanide
|
Samarskite, the name of the mineral from which it was first isolated
|
|
6
|
150.36
|
0.02
|
7.52
|
1345.00
|
2067.00
|
0.20
|
1.17
|
7.05
|
|
Terbium
|
Tb
|
65
|
Lanthanide
|
Ytterby, Sweden
|
|
6
|
158.93
|
0.00
|
8.23
|
1629.00
|
3503.00
|
0.18
|
1.20
|
1.20
|
|
Gadolinium
|
Gd
|
64
|
Lanthanide
|
Johan Gadolin, chemist, physicist and mineralogist
|
|
6
|
157.25
|
0.03
|
7.90
|
1585.00
|
3546.00
|
0.24
|
1.20
|
6.20
|
|
Europium
|
Eu
|
63
|
Lanthanide
|
Europe
|
|
6
|
151.96
|
0.00
|
5.24
|
1099.00
|
1802.00
|
0.18
|
1.20
|
2.00
|