Promethium – Discoverer – Year of Discovery

Periodic Table of Elements - discoverer
1
H

Hydrogen

1766

2
He

Helium

1895

3
Li

Lithium

1817

4
Be

Beryllium

1797

5
B

Boron

1808

6
C

Carbon

unknown

7
N

Nitrogen

1772

8
O

Oxygen

1774

9
F

Fluorine

1886

10
Ne

Neon

1898

11
Na

Sodium

1807

12
Mg

Magnesium

1755

13
Al

Aluminium

1825

14
Si

Silicon

1824

15
P

Phosphorus

1669

16
S

Sulfur

unknown

17
Cl

Chlorine

1774

18
Ar

Argon

1894

19
K

Potassium

1807

20
Ca

Calcium

1808

21
Sc

Scandium

1879

22
Ti

Titanium

1791

23
V

Vanadium

1801

24
Cr

Chromium

1797

25
Mn

Manganese

1774

26
Fe

Iron

unknown

27
Co

Cobalt

1735

28
Ni

Nickel

1751

29
Cu

Copper

unknown

30
Zn

Zinc

unknown

31
Ga

Gallium

1875

32
Ge

Germanium

1886

33
As

Arsenic

unknown

34
Se

Selenium

1817

35
Br

Bromine

1826

36
Kr

Krypton

1898

37
Rb

Rubidium

1861

38
Sr

Strontium

1790

39
Y

Yttrium

1789

40
Zr

Zirconium

1789

41
Nb

Niobium

1801

42
Mo

Molybdenum

1778

43
Tc

Technetium

1937

44
Ru

Ruthenium

1844

45
Rh

Rhodium

1803

46
Pd

Palladium

1803

47
Ag

Silver

unknown

48
Cd

Cadmium

1817

49
In

Indium

1863

50
Sn

Tin

unknown

51
Sb

Antimony

unknown

52
Te

Tellurium

1782

53
I

Iodine

1811

54
Xe

Xenon

1898

55
Cs

Caesium

1860

56
Ba

Barium

1808

57-71

 

Lanthanoids

 

72
Hf

Hafnium

1923

73
Ta

Tantalum

1802

74
W

Tungsten

1783

75
Re

Rhenium

1925

76
Os

Osmium

1803

77
Ir

Iridium

1803

78
Pt

Platinum

1735

79
Au

Gold

unknown

80
Hg

Mercury

unknown

81
Tl

Thallium

1861

82
Pb

Lead

unknown

83
Bi

Bismuth

unknown

84
Po

Polonium

1898

85
At

Astatine

1940

86
Rn

Radon

1900

87
Fr

Francium

1939

88
Ra

Radium

1898

89-103

 

Actinoids

 

104
Rf

Rutherfordium

1964

105
Db

Dubnium

1967

106
Sg

Seaborgium

1974

107
Bh

Bohrium

1976

108
Hs

Hassium

1984

109
Mt

Meitnerium

1982

110
Ds

Darmstadtium

1994

111
Rg

Roentgenium

1994

112
Cn

Copernicium

1996

113
Nh

Nihonium

2004

114
Fl

Flerovium

1998

115
Mc

Moscovium

2004

116
Lv

Livermorium

2001

117
Ts

Tennessine

2010

118
Og

Oganesson

2002

57
La

Lanthanum

1839

58
Ce

Cerium

1803

59
Pr

Praseodymium

1885

60
Nd

Neodymium

1885

61
Pm

Promethium

1944

62
Sm

Samarium

1879

63
Eu

Europium

1901

64
Gd

Gadolinium

1880

65
Tb

Terbium

1843

66
Dy

Dysprosium

1886

67
Ho

Holmium

1879

68
Er

Erbium

1842

69
Th

Thulium

1879

70
Yb

Ytterbium

1878

71
Lu

Lutetium

1807

89
Ac

Actinium

1899

90
Th

Thorium

1829

91
Pa

Protactinium

1913

92
U

Uranium

1789

93
Np

Neptunium

1940

94
Pu

Plutonium

1940

95
Am

Americium

1944

96
Cm

Curium

1944

97
Bk

Berkelium

1949

98
Cf

Californium

1950

99
Es

Einsteinium

1952

100
Fm

Fermium

1952

101
Md

Mendelevium

1955

102
No

Nobelium

1958

103
Lr

Lawrencium

1961

Promethium – Discoverer – Year of Discovery

Discoverer of Promethium – Marinsky, Jacob A. & Coryell, Charles D. & Glendenin, Lawerence. E..

Promethium was discovered in 1944.

 

Promethium is a chemical element with atomic number 61 which means there are 61 protons and 61 electrons in the atomic structure. The chemical symbol for Promethium is Pm.

Promethium is one of only two such elements that are followed in the periodic table by elements with stable forms. All of its isotopes are radioactive. In nuclear reactors, promethium equilibrium exists in power operation. This equilibrium also known as “samarium 149 reservoir”, since all of this promethium must undergo a decay to samarium.