Question
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.
  1. What is element X?
  2. Name the allotrope Y.
  3. State whether allotrope Y is a good conductor or non-conductor of electricity.
  4. Name one use of allotrope Y (other than lubrication and pencil leads)
  5. Name two other allotropes of element X.

Answer

  1. Element X: Carbon.
  2. Allotrope Y: Graphite.
  3. Y is a good conductor of electricity.
  4. Y is used for making graphite electrodes or carbon electrodes in dry cells.
  5. Allotropes of X: Diamond and buckminsterfullerene.

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