Colored Candle Experiment

Colored candles
Does wax color affect how candles burn?

The classic colored candle experiment - to test whether or not the dye in candles affects burn time - is a popular choice for science fairs, class projects, and homeschool lessons. Tests involving the colors of candles are some of the most common projects. There are several ways to perform this experiment and other experiments related to candle color. Learn how to use this easy variable as part of a great learning experience.

Classic Colored Candle Experiment

The most common experiment with colored candles is to test different colors to see if the burn time of a candle is affected by the dyes in the wax, such as discovering do white candles burn faster than colored candles or vice versa. This experiment can be performed in different ways, but the basic procedure is as follows.

  1. Choose a white or colorless candle as the control against which to compare how colored candles burn. Any size or shape candle can be used, but tea lights and tapers are the most popular and can be the easiest to find.
  2. Select one or more colored candles to burn. These candles should be from the same manufacturer as the control candle, and all the candles should be the same size and shape. For a more thorough experiment, choose several different candle colors to work with.
  3. Create a hypothesis about how dye will affect a candle's burn time. This is the basis of the experiment and the hypothesis should be worded to describe the effect you believe the dye will have, whether you think colored candles will burn faster or slower than colorless candles.
  4. Decide how to judge the candles' burn time. If you are using tapers, you can measure the candles during the experiment, or you can mark equal length intervals on the candle with a permanent marker and time how long it takes each color of candle to burn down to that point. If you choose tea lights, the easiest way to judge the burn time accurately is to time how long it takes each candle to burn out completely.
  5. Trim the wicks of each candle to an equal length, and place them on a heat resistant surface. Be sure to conduct the experiment in an area free from drafts, and keep the candles at least 10 inches apart so the heat from each candle's burning does not affect other candles.
  6. Light the colorless and colored candles simultaneously and begin timing how they burn. You may choose to check the candles at equal intervals - every five minutes, for example - to see how much they have burned, or you may choose to watch the marks you have put on the side of the candle to see how quickly each one burns.
  7. Record your measurements, using a timer if necessary to ensure accuracy. If you are going to note when the candles burn out completely, watch them carefully so you do not miss when they are finished burning.
  8. After the experiment is complete, analyze your data. You may create a graph of how long each candle burned and how much wax was consumed, or you may write a paper or report discussing your results. Be sure to compare your results with your initial hypothesis to see how accurate your predictions were.

More Options for Experimenting With Colored Candles

While studying how dye affects the burn time of a candle is a popular option, it is not the only suitable project. Other interesting options include studying how a candle's color affects:

  • Flame height
  • Flame color or brightness
  • Soot production
  • Flame temperature

These experiments can be more difficult than just judging burn time, and it is essential to use the proper equipment for each one. Lengthy experiments involving burning candles should never be left unattended, and they should always be conducted with proper adult supervision.

Other Candle Variables to Test

If a colored candle experiment isn't interesting enough, other candle characteristics can be easily tested with basic projects as well. Consider questions such as:

  • How does a candle's shape affect how long it burns compared to a candle that is the same weight but a different shape?
  • Do scented candles burn faster or slower than unscented candles, and does the quality of scent affect the burn time?
  • What type of candle wax - soy, paraffin, beeswax, etc. - burns fastest or slowest?
  • Does the room temperature or candle temperature affect the candle's burn time?
  • Do old candles burn faster or slower than candles that are brand new?

Experiments to answer these questions are similar to colored candle experiments, but each procedure should be adjusted to isolate the variable being tested.

Tips for Experimenting With Candles

Whether you want to experiment with colored candles or try any other science projects about burning candles, safety should always be considered.

  • Children should be closely supervised when experimenting with burning candles.
  • A glass of water or fire extinguisher should be available nearby.
  • Only burn candles on heat resistant surfaces away from any flammable materials.
  • Conduct multiple tests of the experiment to average your results for a more accurate conclusion.
  • Minimize other project variables by choosing candles from the same manufacturer that are the same size, shape, and weight for accurate comparisons.

By carefully planning an experiment from your hypothesis to analyzing the data you collect, you can learn how candle color impacts the candle's burn time or other characteristics, and you can learn to better appreciate the candles you enjoy.

Colored Candle Experiment