Diamond and graphite. Are made of carbon why they have different properties graphite conduct. Electricity but diamond do not conduct electricity
Answers
Answer:Graphite can conduct electricity because of the delocalised (free)
electrons in its structure. These arise because each carbon atom is only
bonded to 3 other carbon atoms. This leaves 1 electron to become
delocalised. However, in diamond, all 4 outer electrons on each carbon
atom are used in covalent bonding, so there are no delocalised electrons.
Both diamond and graphite are made entirely out of carbon, as is the more recently discovered buckminsterfullerene (a discrete soccer-ball-shaped molecule containing carbon 60 atoms). The way the carbon atoms are arranged in space, however, is different for the three materials, making them allotropes of carbon. The differing properties of carbon and diamond arise from their distinct crystal structures.
In a diamond, the carbon atoms are arranged tetrahedrally. Each carbon atom is attached to four other carbon atoms 1.544 x 10-10 meter away with a C-C-C bond angle of 109.5 degrees. It is a strong, rigid three-dimensional structure that results in an infinite network of atoms. This accounts for diamond's hardness, extraordinary strength and durability and gives diamond a higher density than graphite (3.514 grams per cubic centimeter). Because of its tetrahedral structure, diamond also shows a great resistance to compression. The hardness of a crystal is measured on a scale, devised by Friedrich Mohs, which ranks compounds according to their ability to scratch one another. Diamond will scratch all other materials and is the hardest material known (designated as 10 on the Mohs scale). It is the best conductor of heat that we know, conducting up to five times the amount that copper does. Diamond also conducts sound, but not electricity; it is an insulator, and its electrical resistance, optical transmissivity and chemical inertness are correspondingly remarkable.
The carbon atoms in graphite are also arranged in an infinite array, but they are layered. These atoms have two types of interactions with one another. In the first, each carbon atom is bonded to three other carbon atoms and arranged at the corners of a network of regular hexagons with a 120-degree C-C-C bond angle. These planar arrangements extend in two dimensions to form a horizontal, hexagonal "chicken-wire" array. In addition, these planar arrays are held together by weaker forces known as stacking interactions. The distance between two layers is longer (3.347 x 10-10 meter) than the distance between carbon atoms within each layer (1.418 x 10-10 meter). This three-dimensional structure accounts for the physical properties of graphite. Unlike diamond, graphite can be used as a lubricant or in pencils because the layers cleave readily. It is soft and slippery, and its hardness is less than one on the Mohs scale. Graphite also has a lower density (2.266 grams per cubic centimeter) than diamond. The planar structure of graphite allows electrons to move easily within the planes. This permits graphite to conduct electricity and heat as well as absorb light and, unlike diamond, appear black in color.
Properties of Graphite:
i) Inside the each layer of Graphite, The free electrons movies continuously. Due to which, Graphite is a good conductor of electricity.
ii) Graphite is found in nature as free state is black, Slippery and Brittle.
iii) Density of Graphite is .9 to 2.3g/cm^3
iv) Graphite is mostly used in making all leads and extract of writing pencils.
v) Like diamond, Graphite also doesn't dissolve in any solvent.
Properties of Diamond:
i) Density of Diamond is 3.5g/cm^3
ii) Melting point of diamond is 3500 degree Celsius.
iii) There is no effect of Acids and bases on diamond.
iv) Diamond doesn't dissolve in any solvent.
v) Diamond is bad conductor of electricity; As it does not have free electrons.
vi) When diamond is heated at 800 degree Celsius in presence of oxygen, then only it released the CO2.
Uses of Diamond:
i) Diamond is used in ornaments and decoration.
ii) Diamond is used for Glass cutting and rock drilling machines.
iii) Diamond is used in making eye surgery knives.
iv) Diamond dust is used for polishing of other diamonds.
v) Diamonds is used in Space-crafts and Satellites to prevent radiations.
Uses of Graphite:
i) Graphite is used in writing pencils and Lead of Lead pencils.
ii) Graphite is used in making of Lubricants and Light bulbs.
iii) Graphite is used for making Carbon electrodes.
iv) Graphite is uses in Arc lamps to make the light more brighter and effective.
v) Graphite is used in paints and polish to give a better look.
"By considering points of Diamond and Graphite, You can compare/differ between Diamond and Graphite. "
Q. Graphite is utilized in making electrodes due to following properties:
i) Good conductor of Electricity
ii) Keeps the surface look always clean and rough
iii) It is inexpensive; It saves expenses
iv) Insoluble in water, Acids and Bases
v) Have High density
Q. Why Diamond, Silver, Platinum are used in making jwelleries ? :
Gold, Silver, Platinum are used for making Jwelleries. Because they are very precious. And, Only Rich people can afford it. So, Gold, silver, platinum , diamond is used in Jwelleries. As well as, they don't have effect of surrounding and environment. And, it also prevents Ornaments from rusting.
Diamonds are used for making jwelleries because, Diamond is one of the rarest substance found in nature. As it is so Hard and expensive, so only rich people can afford it. Therefore, Diamond is used for making Jwelleries.