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प्रश्न
Explain the following.
Diamond, graphite and fullerenes are crystalline forms of carbon.
उत्तर
- A crystalline form of carbon has a regular and definite arrangement of atoms.
- In a diamond, each carbon atom is linked to four other carbon atoms by covalent bonds. Therefore, a diamond has a tetragonal three-dimensional structure. Hence a regular and definite structure of atoms is found in diamond.
- In graphite, each carbon atom is bonded to three other carbon atoms in such a way that a hexagonal layered structure is formed. Thus, the regular arrangement of atoms in graphite is in layers.
- In fullerene, C60 atoms are joined to each other in pentagonal and hexagonal arrangements. As a result, the structure of fullerene is like a football. The molecules of fullerene are found in the form of buckyballs and buckytubes.
- Since diamond, graphite and fullerene have definite shapes, sharp edges and plane surfaces, they are in crystalline form. Hence, Diamond, graphite and fullerenes are crystalline forms of carbon.
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संबंधित प्रश्न
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bone charcoal
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b. diamond
c. coke
d. amorphous carbon
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.............. is used to make carbon brushes in dynamos.
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A crystalline allotrope of carbon built up from a hexagonal unit.
Complete the statement by filling the blank with the correct word from the option.
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