Chemical Elements

Chemical Elements

Atomic
number
Symbol Name Atomic
mass
State
at STP
Density
at STP
Discovered

1

H

1.00794(4)

gas

0.0000899

1766

2

He

4.002602(2)

gas

0.0001785

1868

3

Li

6.941(2)

solid

0.535

1817

4

Be

9.012182(3)

solid

1.848

1798

5

B

10.811(7)

solid

2.46

1807

6

C

12.0107(8)

solid

2.26

Ancient

7

N

14.0067(2)

gas

0.001251

1772

8

O

15.9994(3)

gas

0.001429

1774

9

F

18.9984032(5)

gas

0.001696

1670

10

Ne

20.1797(6)

gas

0.0009

1898

11

Na

22.98976928(2)

solid

0.968

1807

12

Mg

24.3050(6)

solid

1.738

1808

13

Al

26.9815386(8)

solid

2.7

Ancient

14

Si

28.0855(3)

solid

2.33

1854

15

P

30.973762(2)

solid

1.823

1669

16

S

32.065(5)

solid

1.96

Ancient

17

Cl

35.453(2)

gas

0.003214

1774

18

Ar

39.948(1)

gas

0.001784

1894

19

K

39.0983(1)

solid

0.856

1807

20

Ca

40.078(4)

solid

1.55

Ancient

21

Sc

44.955912(6)

solid

2.985

1876

22

Ti

47.867(1)

solid

4.507

1791

23

V

50.9415(1)

solid

6.11

1803

24

Cr

51.9961(6)

solid

7.14

Ancient

25

Mn

54.938045(5)

solid

7.47

1774

26

Fe

55.845(2)

solid

7.874

Ancient

27

Co

58.933195(5)

solid

8.9

Ancient

28

Ni

58.6934(4)

solid

8.908

1751

29

Cu

63.546(3)

solid

8.92

Ancient

30

Zn

65.38(2)

solid

7.14

1746

31

Ga

69.723(1)

solid

5.904

1875

32

Ge

72.64(1)

solid

5.323

1886

33

As

74.92160(2)

solid

5.727

Ancient

34

Se

78.96(3)

solid

4.819

1817

35

Br

79.904(1)

liquid

3.12

1826

36

Kr

83.798(2)

gas

0.00375

1898

37

Rb

85.4678(3)

solid

1.532

1861

38

Sr

87.62(1)

solid

2.63

1790

39

Y

88.90585(2)

solid

4.472

1794

40

Zr

91.224(2)

solid

6.511

1789

41

Nb

92.90638(2)

solid

8.57

1801

42

Mo

95.96(2)

solid

10.28

1778

43

Tc

[98]

solid

11.5

1937

44

Ru

101.07(2)

solid

12.37

1827

45

Rh

102.90550(2)

solid

12.45

1803

46

Pd

106.42(1)

solid

12.023

1803

47

Ag

107.8682(2)

solid

10.49

Ancient

48

Cd

112.411(8)

solid

8.65

1817

49

In

114.818(3)

solid

7.31

1863

50

Sn

118.710(7)

solid

7.31

Ancient

51

Sb

121.760(1)

solid

6.697

Ancient

52

Te

127.60(3)

solid

6.24

1782

53

I

126.90447(3)

solid

4.94

1811

54

Xe

131.293(6)

gas

0.0059

1898

55

Cs

132.9054519(2)

solid

1.879

1860

56

Ba

137.327(7)

solid

3.51

1808

57

La

138.90547(7)

solid

6.146

1839

58

Ce

140.116(1)

solid

6.689

1803

59

Pr

140.90765(2)

solid

6.64

1885

60

Nd

144.242(3)

solid

7.01

1885

61

Pm

[145]

solid

7.264

1947

62

Sm

150.36(2)

solid

7.353

1853

63

Eu

151.964(1)

solid

5.244

1901

64

Gd

157.25(3)

solid

7.901

1880

65

Tb

158.92535(2)

solid

8.219

1843

66

Dy

162.500(1)

solid

8.551

1886

67

Ho

164.93032(2)

solid

8.795

1878

68

Er

167.259(3)

solid

9.066

1842

69

Tm

168.93421(2)

solid

9.321

1879

70

Yb

173.054(5)

solid

6.57

1878

71

Lu

174.9668(1)

solid

9.841

1907

72

Hf

178.49(2)

solid

13.31

1923

73

Ta

180.94788(2)

solid

16.65

1802

74

W

183.84(1)

solid

19.25

1783

75

Re

186.207(1)

solid

21.02

1925

76

Os

190.23(3)

solid

22.61

1803

77

Ir

192.217(3)

solid

22.65

1803

78

Pt

195.084(9)

solid

21.09

Ancient

79

Au

196.966569(4)

solid

19.3

Ancient

80

Hg

200.59(2)

liquid

13.534

Ancient

81

Tl

204.3833(2)

solid

11.85

1861

82

Pb

207.2(1)

solid

11.34

Ancient

83

Bi

208.98040(1)

solid

9.78

Ancient

84

Po

[209]

solid

9.196

1898

85

At

[210]

solid

(unknown)

1940

86

Rn

[222]

gas

0.00973

1900

87

Fr

[223]

solid

(unknown)

1939

88

Ra

[226]

solid

5

1898

89

Ac

[227]

solid

10.07

1899

90

Th

232.03806(2)

solid

11.724

1828

91

Pa

231.03588(2)

solid

15.37

1913

92

U

238.02891(3)

solid

19.05

1789

93

Np

[237]

solid

20.45

1940

94

Pu

[244]

solid

19.816

1940

95

Am

[243]

solid

(unknown)

1944

96

Cm

[247]

solid

13.51

1944

97

Bk

[247]

solid

14.78

1949

98

Cf

[251]

solid

15.1

1950

99

Es

[252]

solid

(unknown)

1952

100

Fm

[257]

(unknown)

(unknown)

1952

101

Md

[258]

(unknown)

(unknown)

1955

102

No

[259]

(unknown)

(unknown)

1957

103

Lr

[262]

(unknown)

(unknown)

1961

104

Rf

[267]

(unknown)

(unknown)

1969

105

Db

[268]

(unknown)

(unknown)

1967

106

Sg

[271]

(unknown)

(unknown)

1974

107

Bh

[272]

(unknown)

(unknown)

1976

108

Hs

[270]

(unknown)

(unknown)

1984

109

Mt

[276]

(unknown)

(unknown)

1982

110

Ds

[281]

(unknown)

(unknown)

1994

111

Rg

[280]

(unknown)

(unknown)

1994

112

Cn

[285]

(unknown)

(unknown)

1996

113

Nh

[284]

(unknown)

(unknown)

2003

114

Fl

[289]

(unknown)

(unknown)

1998

115

Mc

[288]

(unknown)

(unknown)

2003

116

Lv

[293]

(unknown)

(unknown)

2000

117

Ts

[294]

(unknown)

(unknown)

2010

118

Og

[294]

(unknown)

(unknown)

2002

Notes