Give reason-
1)Carbon compounds are poor conductors of electricty
2)Diamond is hard while graphite is soft
Give reason-
1)Carbon compounds are poor conductors of electricty
2)Diamond is hard while graphite is soft
(A) Carbon forms covalent compounds. The electrons in the outermost shell of the covalent compounds are shared by the nearby atoms. As there are no free electrons (only at absolute zero) for conducting electricity, the covalent compounds are perfect insulators at absolute zero. As the temperature increases, some electrons move from valence band to conduction band. This gives rise to the conductivity. But, as the number of charge carriers are very low, carbon is poor conductor.
(B) In diamond each carbon atom is covalently bonded to four other carbon atoms.This arrangement of carbon atoms gives rise to a tetrahedral structure. These small tetrahedrons combine to form a rigid three dimensional network.
In graphite, carbon atoms are bonded together in flat layers by strong covalent bonds in a regular hexagon . These layers are held together by much weaker van der Waals” forces, therefore the crystals of graphite are soft and slippery.
(A) Carbon forms covalent compounds. The electrons in the outermost shell of the covalent compounds are shared by the nearby atoms. As there are no free electrons (only at absolute zero) for conducting electricity, the covalent compounds are perfect insulators at absolute zero. As the temperature increases, some electrons move from valence band to conduction band. This gives rise to the conductivity. But, as the number of charge carriers are very low, carbon is poor conductor.
(B) In diamond each carbon atom is covalently bonded to four other carbon atoms.This arrangement of carbon atoms gives rise to a tetrahedral structure. These small tetrahedrons combine to form a rigid three dimensional network.
In graphite, carbon atoms are bonded together in flat layers by strong covalent bonds in a regular hexagon . These layers are held together by much weaker van der Waals” forces, therefore the crystals of graphite are soft and slippery.
