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Question
An element E exists in three allotropic forms A, B and C. In allotrope A, the atoms of element E are joined to form spherical molecules. In allotrope B, each atom of element E is surrounded by three other E atoms to form a sheet like structure. In allotrope C, each atom of element E is surrounded by four other E atoms to form a rigid structure.
(a) Name the element E.
(b) What is allotrope A.
(c) What is allotrope B?
(d) What is allotrope C?
(e) Which allotrope is used in making jewellery?
(f) Which allotrope is used in making anode of a dry cell?
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Solution
(a) Carbon is the element 'E' which exists in three allotropic forms A, B and C.
(b) Buckminsterfullerene is the allotrope, A, of carbon in which the atoms are joined to form spherical molecules.
(c) Graphite is the allotrope, B, of carbon which is surrounded by three other carbon atoms to form a sheet like structure.
(d) Diamond is the allotrope, C, of carbon in which each atom is surrounded by four other carbon atoms to form a rigid structure.
(e) The allotrope C (Diamond) is used to make jewellery.
(f) The allotrope B (Graphite) is used in making anode of a dry cell.
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