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Comparing the burning speed of scented and unscented candlesFeatured science projectScience project video


This experiment was performed to compare how quickly a scented and an unscented candle will burn. The tests were done by comparing the length that the candles will burn in 30 minutes - using unscented, rose scented and apple scented candles.


Unscented candles burn more quickly than scented candles.

Scientific Terms

Paraffin wax, wick, capillary action, vaporized



Candles are a convenient way of providing light and heat when no electricity is available. They are normally made from paraffin wax with a wick in the middle. Candles can also be made from soy wax or other plant wax, animal fat or bee wax. Wax acts as a fuel to keep the candle burning. The wick has to be an absorbent twine with strong capillary ability.

When the wick of a candle is lit, the heat from the flame will melt the wax surrounding the wick. The melted wax will be absorbed by the wick and the capillary action will pull the wax upwards. When the wax approaches the flame, it will start to vaporize and the vaporized wax will start to burn. The wick itself will not burn because the vaporizing wax will cool the wick.

Candle manufacturers produce both scented and unscented candles. Common scents used in candles include kitchen aromas such as vanilla, fruit scents, flower scents, spa scents like green tea and ocean breeze. Candles are also found in a variety of colors, shapes and sizes.

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Complexity level:
Project cost ($):
Time required:
1 hour to prepare, 1 hour for the science project experiment
Material availability:
Easily found. Candles can be purchased at a supermarket or department store.
Safety concerns:

Be careful when handling fire. Ensure that the experiment is conducted in a well-ventilated laboratory or in a safe location, with no flammable materials lying around. Adult assistance is required.