鈷是什麼?(英文答案)

Cobalt is a hard, lustrous, silver-gray metal, a chemical element with symbol Co. It is found in various ores, and is used in the preparation of magnetic, wear-resistant, and high-strength alloys. Its compounds are used in the production of inks, paints, and varnishes.








27
iron ← cobalt → nickel

-
↑
Co
↓
Rh







圖片參考：http://upload.wikimedia.org/wikipedia/commons/9/9e/Co-TableImage.png

Periodic Table - Extended Periodic Table

General

Name, Symbol, Number
cobalt, Co, 27

Chemical series
transition metals

Group, Period, Block
9, 4, d

Appearance
metallic with gray tinge

圖片參考：http://upload.wikimedia.org/wikipedia/commons/thumb/5/51/Co%2C27.jpg/125px-Co%2C27.jpg


Atomic mass
58.933195(5)  g·mol−1

Electron configuration
[Ar] 4s2 3d7

Electrons per shell
2, 8, 15, 2

Physical properties

Density (near r.t.)
8.90  g·cm−3

Liquid density at m.p.
7.75  g·cm−3

Melting point
1768 K
(1495 °C, 2723 °F)

Boiling point
3200 K
(2927 °C, 5301 °F)

Heat of fusion
16.06  kJ·mol−1

Heat of vaporization
377  kJ·mol−1

Heat capacity
(25 °C) 24.81  J·mol−1·K−1



Vapor pressure


P(Pa)
1
10
100
1 k
10 k
100 k

at T(K)
1790
1960
2165
2423
2755
3198

Atomic properties

Crystal structure
hexagonal

Oxidation states
2, 3
(amphoteric oxide)

Electronegativity
1.88 (Pauling scale)

Ionization energies
(more)
1st:  760.4  kJ·mol−1

2nd:  1648  kJ·mol−1

3rd:  3232  kJ·mol−1

Atomic radius
135  pm

Atomic radius (calc.)
152  pm

Covalent radius
126  pm

Miscellaneous–

Magnetic ordering
ferromagnetic

Electrical resistivity
(20 °C) 62.4 n Ω·m

Thermal conductivity
(300 K) 100  W·m−1·K−1

Thermal expansion
(25 °C) 13.0  µm·m−1·K−1

Speed of sound (thin rod)
(20 °C) 4720 m/s

Young's modulus
209  GPa

Shear modulus
75  GPa

Bulk modulus
180  GPa

Poisson ratio
0.31

Mohs hardness
5.0

Vickers hardness
1043  MPa

Brinell hardness
700  MPa

CAS registry number
7440-48-4

Selected isotopes



Main article: Isotopes of cobalt


iso
NA
half-life
DM
DE (MeV)
DP

56Co
syn
77.27 d
ε
4.566
56Fe

57Co
syn
271.79 d
ε
0.836
57Fe

58Co
syn
70.86 d
ε
2.307
58Fe

59Co
100%
Co is stable with 32 neutrons

60Co
syn
5.2714 years
β-
2.824
60Ni

References
Notable characteristics
Cobalt is ferromagnetic with atomic number 27. The Curie temperature is of 1388 K with 1.6~1.7 Bohr magnetons per atom. It is frequently associated with nickel, and both are characteristic ingredients of meteoric iron. Mammals require small amounts of cobalt salts. Cobalt-60, an artificially produced radioactive isotope of cobalt, is an important radioactive tracer and cancer-treatment agent. Cobalt has a relative permeability two thirds that of iron. Metallic cobalt commonly presents a mixture of two crystallographic structures hcp and fcc with a transition temperature hcp→fcc of 722 K.
Common oxidation states of cobalt include +2 and +3, though +1 is also seen.

[edit] Applications

Alloys, such as:

Superalloys, for parts in gas turbine aircraft engines.
Corrosion- and wear-resistant alloys.
High speed steels.
Cemented carbides (also called hard metals) and diamond tools.
Magnets and magnetic recording media.

Alnico magnets.
Catalysts for the petroleum and chemical industries.
Electroplating because of its appearance, hardness, and resistance to oxidation.
Drying agents for paints, varnishes, and inks.
Ground coats for porcelain enamels.
Pigments (cobalt blue and cobalt green).


圖片參考：http://upload.wikimedia.org/wikipedia/commons/thumb/7/7a/Bristol.blue.glass.arp.750pix.jpg/145px-Bristol.blue.glass.arp.750pix.jpg



圖片參考：http://en.wikipedia.org/skins-1.5/common/images/magnify-clip.png
Cobalt blue glasshttp://en.wikipedia.org/wiki/Cobalt

cobalt (Co)

Cobalt is a hard, lustrous, silver-gray metal, a chemical element with symbol Co. It is found in various ores, and is used in the preparation of magnetic, wear-resistant, and high-strength alloys. Its compounds are used in the production of inks, paints, and varnishes.

鈷的英文是Cobalt.(Co)

cobalt
簡寫(Co)

鈷是化學元素之一，化學符號為Co,
英文好像是cobalt

cobalt