What is The Structure of Graphite?

Structure of Graphite

Graphite has a giant covalent structure in which: each carbon atom is joined to three other carbon atoms by covalent bonds. the carbon atoms form layers with a hexagonal arrangement of atoms. the layers have weak forces between them.

Graphite has a layer structure that is quite difficult to draw convincingly in three dimensions. The diagram below shows the arrangement of the atoms in each layer and the way the layers are spaced.

Solid carbon comes in different forms known as allotropes depending on the type of chemical bond. The two most common are diamond and graphite.

In diamond the bonds are sp3 and the atoms form tetrahedra with each bound to four nearest neighbors. In graphite, they are sp2 orbital hybrids and the atoms form in planes with each bound to three nearest neighbors 120 degrees apart.

The individual layers are called graphene. In each layer, the carbon atoms are arranged in a honeycomb lattice with a bond length of 0.142 nm, and the distance between planes is 0.335 nm. Atoms in the plane are bonded covalently, with only three of the four potential bonding sites satisfied.

Structure of Graphite

The fourth electron is free to migrate in the plane, making graphite electrically conductive. Bonding between layers is via weak van der Waals bonds, which allow layers of graphite to be easily separated, or to slide past each other. Electrical conductivity perpendicular to the layers is consequently about 1000 times lower

Notice that you can’t really draw the side view of the layers to the same scale as the atoms in the layer without one or another part of the diagram is either very spread out or very squashed.

In that case, it is important to give some idea of the distances involved. The distance between the layers is about 2.5 times the distance between the atoms within each layer.

The layers, of course, extend over huge numbers of atoms – not just the few shown above.

You might argue that carbon has to form 4 bonds because of its 4 unpaired electrons, whereas in this diagram it only seems to be forming 3 bonds to the neighboring carbons. This diagram is something of a simplification and shows the arrangement of atoms rather than the bonding.

The Bonding in Graphite

Each carbon atom uses three of its electrons to form simple bonds to its three close neighbors. That leaves the fourth electron at the bonding level. These “spare” electrons in each carbon atom become delocalized over the whole of the sheet of atoms in one layer.

They are no longer associated directly with any particular atom or pair of atoms but are free to wander throughout the whole sheet. The important thing is that the delocalized electrons are free to move anywhere within the sheet – each electron is no longer fixed to a particular carbon atom.

Bonding in Graphite

There is, however, no direct contact between the delocalized electrons in one sheet and those in the neighboring sheets. The atoms within a sheet are held together by strong covalent bonds – stronger, in fact, than in diamond because of the additional bonding caused by the delocalized electrons.

So, what holds the sheets together? In graphite, you have the ultimate example of van der Waals dispersion forces. As the delocalized electrons move around in the sheet, very large temporary dipoles can be set up which will induce opposite dipoles in the sheets above and below – and so on throughout the whole graphite crystal.

Graphite has many properties like a high melting point, similar to that of a diamond. In order to melt graphite, it isn’t enough to loosen one sheet from another. You have to break the covalent bonding throughout the whole structure.

It has a soft, slippery feel, and is used in pencils and as a dry lubricant for things like locks. You can think of graphite rather like a pack of cards – each card is strong, but the cards will slide over each other, or even fall off the pack altogether. When you use a pencil, sheets are rubbed off and stick to the paper. 

Graphite has a lower density than diamond. This is because of the relatively large amount of space that is “wasted” between the sheets.

Graphite is insoluble in water and organic solvents – for the same reason that diamond is insoluble. Attractions between solvent molecules and carbon atoms will never be strong enough to overcome the strong covalent bonds in graphite.

It conducts electricity. The delocalized electrons are free to move throughout the sheets. If a piece of graphite is connected into a circuit, electrons can fall off one end of the sheet and be replaced with new ones at the other end.

FAQs.

What is The Structure of Graphite?

Graphite has a giant covalent structure in which: each carbon atom is joined to three other carbon atoms by covalent bonds. the carbon atoms form layers with a hexagonal arrangement of atoms. the layers have weak forces between them.

What is the structure of diamond and graphite?

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.

What is the crystal structure of graphite?

Graphite (/ˈɡræfaɪt/), archaically referred to as plumbago, is a crystalline form of the element carbon with its atoms arranged in a hexagonal structure. It occurs naturally in this form and is the most stable form of carbon under standard conditions.

Is graphite a layered structure?

Graphite is composed of layers of carbon atoms that are arranged in 6-membered, hexagonal rings. These rings are attached to one another on their edges.

What is the structure and properties of graphite?

Graphite has a giant covalent structure in which: the carbon atoms form layers of hexagonal rings. there are no covalent bonds between the layers. there is one non-bonded or delocalized – electron from each atom.

What is the structure and bonding of graphite?

Graphite has a giant covalent structure consisting of layers of carbon atoms. Carbon atoms have 4 valence electrons that are available for bonding. In graphite, each carbon atom is covalently bonded to 3 other carbon atoms. Therefore, every carbon atom has 1 electron that is not used for bonding.

Is graphite a simple structure?

The giant covalent structure of graphite. Graphite has a layer structure which is quite difficult to draw convincingly in three dimensions. The diagram below shows the arrangement of the atoms in each layer, and the way the layers are spaced.

Is graphite a tetrahedral structure?

Graphite has a tetrahedral structure is not correct. Graphite is a naturally-occurring form of crystalline carbon. It is found in metamorphic and igneous rocks. Graphite is formed when carbon is subjected to heat and pressure in Earth’s crust and in the upper mantle.

What is graphite giving its structure and uses?

Graphite is an allotrope of carbon. graphite each carbon Atom is linked with 3 other carbon atoms by single covalent bond resulting in the hexagonal ring which is arranged in a layer. In general, graphite is used in pencil laid, batteries as an electrode. It has 2-dimensional layers like structure.

What is the name of structure of graphite?

Graphite has a layered structure that consists of rings of six carbon atoms arranged in widely spaced horizontal sheets. Graphite thus crystallizes in the hexagonal system, in contrast to the same element crystallizing in the octahedral or tetrahedral system as diamond.

Which has graphite like structure?

This indicates that the major part of the carbon atoms in BCN(H) network have a structure similar to that of graphite.

How do you structure graphite?

How does the structure of graphite account for its physical properties?

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.

What is graphene structure?

Graphene is a single-atom thick layer of graphite with strong covalent bonds between each carbon atom. The atoms are arranged in hexagons. Its properties include: high melting and boiling points. Graphene’s many covalent bonds are strong and substantial energy is needed to break them.

Is graphite hard or soft?

Graphite is very soft and slippery. Diamond is the hardest substance known to man. If both are made only of carbon what gives them different properties? The answer lies in the way the carbon atoms form bonds with each other.

Does graphite have a network structure?

Diamond and graphite are different forms of the element carbon. They both consist of giant covalent network structures of carbon atoms, joined together by covalent bonds.

What are the two different structural forms of carbon?

When an element exists in more than one crystalline form, those forms are called allotropes; the two most common allotropes of carbon are diamond and graphite.

Why silicon has no graphite structure?

Due to bigger size and smaller electronegativity of Si than C, it does not undergo sp2-hybridization and hence it does not form pπ-pπ double bonds needed for graphite like structure. Instead, it prefers to undergo only sp3-hybridization and hence silicon has diamond like three-dimensional network structure.

What is graphite formula?

The chemical formula of graphite is C, Molecular weight: 12.01. Nanotubes, diamond and graphite are allotropes of carbon, and the chemical formula can be expressed by “C”.

Why is graphite soft in terms of structure and bonding?

Graphite is a form of carbon in which the carbon atoms form covalent bonds with three other carbon atoms. These layers can slide over each other, so graphite is much softer than diamond.

What holds the layers of graphite together?

Although graphite is composed of giant molecules, its atoms are arranged in layers that can slide past one another. Weak Van der Waals forces hold the layers together.

How are the structures of graphite and graphene different?

The key difference between graphite and graphene is that graphite is an allotrope of carbon having a high number of carbon sheets whereas graphene is a single carbon sheet of graphite. One layer out of these layers is a graphene sheet. A graphene sheet is considered as a nanoparticle according to its dimensions.

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