Welcome to Chemistry Connections, my name is Devon Ennis and I am your host for episode 23 called the chemistry of candles. Today I will be discussing what happens to candle wax when the candle is lit and how candle wax is made.
Segment 1: Introduction to candles
I introduce the topic by describing where the earliest candles were found, and how they were used throughout time. The purpose of candles has changed from being used as a light source to being used for the scent. I also explain some of the materials used to make candles, and ask rhetorical questions about where the wax goes when burning a candle.
Segment 2: The Chemistry Behind candles
Paraffin wax is made from crude oil and is the most common wax used in candles. The wick absorbs the liquid and pulls it upwards towards the flame. The heat from the flame vaporizes the wax. I also explain how the stream of white smoke after you blow out a candle is paraffin vapor that condensed into a visible form.
The feedstock for paraffin wax is slack wax, and the first step to making paraffin wax is to remove the oil from slack wax. The slack wax is heated, mixed with one or more solvents and then cooled. As it cools, the wax crystallizes while the oil is left in the solution. The hydrocarbon C31H64 is a typical component of paraffin wax. I explain how hydrocarbon molecules of different lengths have different behaviors and properties.
Segment 3: Personal Connections
I used candles all the time, and I’ve always been interested in how candles are made. As well as what happens to the wax as it burns. I had no idea how long the hydrocarbon chains were in candle wax until I was researching it. I was also surprised to know that it was made from crude oil.
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