About the element ~ Carbon
About the element ~ Carbon
i want to have these information:
**~ BASIC information of Carbon
~ (HOW can change Carbon into diamond)
**~ (element) DIFFERENT between diamond & Carbon
~ OTHER Special characteristic of Carbon
~~~must be in ENGLISH~~~
- ?Lv 41 十年前最愛解答
Atomic Number: 6
Atomic Weight: 12.0107
Melting Point: 3823 K (3550°C or 6422°F)
Boiling Point: 4098 K (3825°C or 6917°F)
Density: 2.2670 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Non-metal
Period Number: 2 Group Number: 14 Group Name: none
What's in a name? From the Latin word for charcoal, carbo.
Say what? Carbon is pronounced as KAR-ben.
Carbon, the sixth most abundant element in the universe, has been known since ancient times. Carbon is most commonly obtained from coal deposits, although it usually must be processed into a form suitable for commercial use. Three naturally occurring allotropes of carbon are known to exist: amorphous, graphite and diamond.
Amorphous carbon is formed when a material containing carbon is burned without enough oxygen for it to burn completely. This black soot, also known as lampblack, gas black, channel black or carbon black, is used to make inks, paints and rubber products. It can also be pressed into shapes and is used to form the cores of most dry cell batteries, among other things.
Graphite, one of the softest materials known, is a form of carbon that is primarily used as a lubricant. Although it does occur naturally, most commercial graphite is produced by treating petroleum coke, a black tar residue remaining after the refinement of crude oil, in an oxygen-free oven. Naturally occurring graphite occurs in two forms, alpha and beta. These two forms have identical physical properties but different crystal structures. All artificially produced graphite is of the alpha type. In addition to its use as a lubricant, graphite, in a form known as coke, is used in large amounts in the production of steel. Coke is made by heating soft coal in an oven without allowing oxygen to mix with it. Although commonly called lead, the black material used in pencils is actually graphite.
Diamond, the third naturally occurring form of carbon, is one of the hardest substances known. Although naturally occurring diamond is typically used for jewelry, most commercial quality diamonds are artificially produced. These small diamonds are made by squeezing graphite under high temperatures and pressures for several days or weeks and are primarily used to make things like diamond tipped saw blades. Although they posses very different physical properties, graphite and diamond differ only in their crystal structure.
A fourth allotrope of carbon, known as white carbon, was produced in 1969. It is a transparent material that can split a single beam of light into two beams, a property known as birefringence. Very little is known about this form of carbon.
- 1 十年前
Atomic number: 6
Atomic weight: 12.0107 (8) g r
CAS Registry ID: 7440-44-0
Group number: 14
Group name: (none)
Period number: 2
Here is a brief description of carbon.
Standard state: solid at 298 K
Colour: graphite is black, diamond is colourless
carbon is available in several forms including amorphous, powder, graphite rods, diamond, "bucky tubes", foil, sheet, and wire. Small and large samples of carbon foil, sheet, and wire can be purchased from Advent Research Materials via their web catalogue.
This sample is from The Elements Collection, an attractive and safely packaged collection of the 92 naturally occurring elements that is available for sale.
Carbon is a Group 14 element. Carbon is distributed very widely in nature. It is found in abundance in the sun, stars, comets, and atmospheres of most planets. The atmosphere of Mars contains 96 % CO2.
Carbon is found free in nature in three allotropic forms: amorphous, graphite, and diamond (further details). Graphite is one of the softest known materials while diamond is one of the hardest. Carbon, as microscopic diamonds, is found in some meteorites. Natural diamonds are found in ancient volcanic "pipes" such as found in South Africa. Diamonds are also recovered from the ocean floor off the Cape of Good Hope.
Diamonds typically crystallize in the face-centered cubic crystal system (space group ) and consist of tetrahedrally bonded carbon atoms. The unit cell of diamond has a two atom basis at (0,0,0) and (1/4,1/4,1/4), which means half of the atoms are at lattice points and the other half are offset by (1/4,1/4,1/4), where 1 is the length of a side of the unit cell. Diamond's density is 3.52 g·cm−3.
The tetrahedral arrangement of atoms is the source of many of diamond’s properties. The carbon atoms in Graphite, the other major allotrope of carbon, display a different (nontetrahedral) connectivity and as a result shows dramatically different physical characteristics: graphite is a soft, dark gray, opaque mineral. Other elements of the carbon group such as silicon crystalize like diamond.
Each carbon atom is covalently bonded to three other surrounding carbon atoms. The flat sheets of carbon atoms are bonded into hexagonal structures. These exist in layers, which are not covalently connected to the surrounding layers. Instead, different layers are connected together by weak forces called the van der Waals forces.
The unit cell dimensions are a = b = 245.6 picometres, c = 669.4 pm. The carbon-carbon bond length in the bulk form is 141.8 pm, and the interlayer spacing is c/2 = 334.7 pm.
Crystal structure of graphiteEach carbon atom possesses an sp2 orbital hybridisation. The pi orbital electrons delocalized across the hexagonal atomic sheets of carbon contribute to graphite's conductivity. In an oriented piece of graphite, conductivity parallel to these sheets is greater than that perpendicular to these sheets.
The bond between the atoms within a layer is strong but the force between two layers of graphite is weak. Therefore, layers of it can slip over each other making it soft.
- 匿名1 十年前
Name, Symbol, Number carbon, C, 6
Chemical series nonmetals
Group, Period, Block 14, 2, p
Appearance black (graphite)
Atomic mass 12.0107(8) g/mol
Electron configuration 1s2 2s2 2p2
Electrons per shell 2, 4
Density (near r.t.) (graphite) 2.267 g·cm−3
Density (near r.t.) (diamond) 3.513 g·cm−3
Melting point ? triple point, ca. 10 MPa
and (4300–4700) K
Boiling point ? subl. ca. 4000 K
(3727 °C, 6740 °F)
Heat of fusion (graphite) ? 100 kJ·mol−1
Heat of fusion (diamond) ? 120 kJ·mol−1
Heat of vaporization ? 355.8 kJ·mol−1
Heat capacity (25 °C) (graphite)
Heat capacity (25 °C) (diamond)
Vapor pressure (graphite) P/Pa 1 10 100 1 k 10 k 100 k
at T/K 2839 3048 3289 3572 3908
Crystal structure hexagonal
Oxidation states 4, 2
(mildly acidic oxide)
Electronegativity 2.55 (Pauling scale)
(more) 1st: 1086.5 kJ·mol−1
2nd: 2352.6 kJ·mol−1
3rd: 4620.5 kJ·mol−1
Atomic radius 70 pm
Atomic radius (calc.) 67 pm
Covalent radius 77 pm
Van der Waals radius 170 pm
Magnetic ordering diamagnetic
Thermal conductivity (300 K) (graphite)
Thermal conductivity (300 K) (diamond)
Thermal diffusivity (300 K) (diamond)
Mohs hardness (graphite) 1-2
Mohs hardness (diamond) 10.0
CAS registry number 7440-44-0
Main article: Isotopes of carbon iso NA half-life DM DE (MeV) DP
12C 98.9% C is stable with 6 neutrons
13C 1.1% C is stable with 7 neutrons
14C trace 5730 y beta- 0.156 14N