In this activity, students take a closer look at a candle flame as an example of a flame that occurs in most natural fires and observe and investigate the flame and the process of burning.

By the end of this activity, students should be able to:

  • appreciate the importance of observation (seeing and describing, not just looking) for scientists.
  • identify the components of a diffusion flame (in a candle)
  • develop ideas about the combustion process – the candle wax is melting, becoming a liquid, then the liquid vaporises into a volatile gas, which ignites when at ignition temperature.
  • understand that the white smoke contains these volatile gases
  • understand that black smoke contains unburnt particles – soot
  • understand that fire needs oxygenheat and fuel – depriving a fire from oxygen causes extinguishment.

Download the Word file (see link above) for:

  • introduction/background notes
  • what you need
  • what to do.

Nature of Science

Scientists observe phenomena very closely and carefully – seeing and describing everything – to help them understand what is happening.

    Published 18 November 2009