A solid element X has four electrons in the outermost shell of its atom. An allotrope Y of this element is used as a dry lubricant in machinery and also in making pencil leads.(a) What is element X?
(b) Name the allotrope Y.
(c) State whether allotrope Y is a good conductor or non-conductor of electricity.
(d) Name one use of allotrope Y (other than lubrication and pencil leads)
(e) Name two other allotropes of element X.
(a) Element X is Carbon as it has four electrons in the outermost shell of its atom.
(b) Allotrope Y is Graphite as it is used as a dry lubricant in machinery and also in making pencil leads.
(c) Y (Graphite) is a good conductor of electricity.
(d) Y (Graphite) is used for making graphite electrodes or carbon electrodes in dry cells.
(e) Allotropes of X (Carbon) is Diamond and buckminsterfullerene.
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