Syllabus bites Electricity

‘Lead’ pencils

Real lead has not been used to make markings for a very long time, and it has never been used in pencils. This is a good thing, because lead is toxic. ABC Science1 is a source of further information.

The ‘lead’ in our pencils is really a type of carbon called graphite2.

Carbon is interesting to us because it conducts electricity – sort of. Electricity can get through, but not easily.

Warning icon

If you connect a pencil into a circuit, be careful – it might get hot! Electrons give up some of their energy as they move through graphite in the form of heat.

Links

  1. http://www.abc.net.au/science/articles/2004/09/09/1195234.htm
  2. http://drawsketch.about.com/od/drawingglossary/g/graphite.htm