The Candle that Lights My Dinner Table

Chemistry in the Science We See

Photo by Rebecca Peterson-Hall on Unsplash

It seemed only fitting that my first article explores the chemistry behind the illuminating candle as it was my example in my introductory article for this new series. If you aren’t sure which article I’m referring to, I’ve linked it here.

Now, to get into the chemistry of candles. For the purpose of visualizing what I’m going to be describing, picture a glass jar filled three-quarters full with a deep red wax and a thin, braided white wick standing a quarter inch from the wax surface. The same principles apply to all candles, but now we can all have the same imagery as we break down what’s happening as you light the cinnamon candle while setting the dinner table with new ceramic plates and the wine glasses you saved for a special occasion.

After bringing the lighter to meet the standing wick in the center of the candle and pausing for ignition, the braided wick directs the flame down to the inflammable wax that contains the scent you’re hoping will fill your room. The important feature of the wax is that its melting point is below the temperature of the flame so that, as the flame is held closed to it, it begins to melt. As it melts, you’ll see the reflective puddle beginning to form on the surface.

The puddle is then slowly carried up the absorbent wick and into the flame. The wick is like a cloth or paper towel you set on a spilled drink, where it absorbs the liquid directly over the puddle first. The liquid then spreads out throughout the cloth, reaching the edges if left long enough. In a similar way, the liquid wax will be absorbed by the base of the wick that is in direct contact with the puddle, then the liquid will creep up the wick to enter the flame.

In the flame, the liquid wax will take energy from the hot fire and eventually absorb enough to energize the molecules into the gas phase. Once in the gaseous state, the molecules are able to bounce around the room and fill the space with the scent. It is the gas particles that are able to reach the receptors in our nose and allow us to detect a smell. As you watch the puddle forming on your candle, the smell of warm cinnamon hits your nose, reminding you of the memory or dream of a quiet Sunday morning where you wake up to a gentle rain tapping…