Hafnium

Properties
Atomic symbol |  Hf
Atomic number |  72
Classification |  Transition Metals
Atomic mass |  178.49 amu
Other Information
Date of discovery |  1923
Name of discoverer |  Dirk Coster & Georg von Hevesy
Name origin |  From the Latin name for Copenhagen, Hafnia.
Uses |  Due to its ability to absorb neutrons, used in reactor control rods and also as a gas scavenger in vacuum tubes.
Obtained from |  Obtained as a by-product of zirconium refining.

Hafnium is considered to be non-toxic. When in powder form it is pyrophoric (which means, it can spontaneously ignite).

## Properties[edit]

Hafnium is a shiny, ductile (that is, it can be drawn out into wire) metal. Chemically this is very similar to the element zirconium. Hafnium is unaffected by all alkalis and all acids other than from hydrogen fluoride. It does reacts with the halogens to form tetrahalides, and at high temperatures it reacts with carbon, boron, oxygen, nitrogen, sulfur and silicon.[1]

## Uses[edit]

Pure Hafnium is used primarily in nuclear reactor control rods. However, its alloys are much more useful. Hafnium carbide is used to line high temperature furnaces, for example.[2]

## References[edit]

1. ↑ http://www.chemicool.com/elements/hafnium.html
2. ↑ http://www.chemicool.com/elements/hafnium.html

Periodic Table of the Elements

1  | 2  | 3  | 4  | 5  | 6  | 7  | 8  | 9  | 10  | 11  | 12  | 13  | 14  | 15  | 16  | 17  | 18

1.008

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

4.003

6.939

9.0122

|  |  |  |  |  |  |  |  |  |  |

10.811

12.011

14.007

15.999

18.998

10.183

22.99

24.312

|  |  |  |  |  |  |  |  |  |  |

26.982

28.086

30.974

32.064

35.453

39.948

39.102

40.08

44.956

47.9

50.942

51.996

54.938

55.847

58.933

58.71

63.546

65.37

69.72

72.59

74.922

78.96

79.904

83.8

85.47

87.62

88.905

91.22

92.906

95.94

[97]

101.07

102.91

106.4

107.87

112.4

114.82

118.69

121.75

127.6

126.9

131.3

132.91

137.34

57*

138.91

178.49

180.95

183.85

186.2

190.2

192.2

195.09

196.97

200.59

204.37

207.19

208.98

210

210

222

215

226.03

89**

227.03

104

[261]

105

[262]

106

[266]

107

[264]

108

[265]

109

[268]

110

[271]

111

[272]

112

[277]

113

[284]

114

[289]

115

[288]

116

[292]

117

[293]

118

[294]

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
*Lanthanides  |

140.12

140.91

144.24

145

150.35

151.96

157.25

158.92

162.5

164.93

167.26

168.93

173.04

174.97

|  |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
**Actinides  |

232.04

231

238.03

237.05

239.05

241.06

244.06

249.08

252.08

252.08

100

257.1

101

258.1

102

259.1

103

262.11

|  |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |