An exact equation can’t be given without knowing the exact type of wax being used, but the following is an example of what it would look like: CxHy + (x + y/4) O2 ---> (y/2) H2O + (x) CO2
One molecule I found was C25H52
When you burn a candle, you are performing simple combustion reactions. The oxygen comes from the air and the heat initially comes from an outside source such as a match. When this combustion reaction happens, it makes water and carbon dioxide as shown as well as heat and light energy.
The wick in a candle is also mainly hydrocarbon with oxygen also present and this also burns though at a much slower rate. When you light the wick, you provide a heat source and oxygen from the air. The smoke formed contains carbon dioxide and water and also some soot from inefficient combustion.
When a candle burns, the wax does two things. First it melts, and then it burns. What burns is actually melted wax. The heat of the candle melts the nearby wax, and that melted wax is absorbed by the candle's wick. The melted wax burns on the wick -- the wick itself isn't burning, just the wax on it. However, as the candle burns down, what happens is there isn't enough wax nearby to melt, and so the end of the wick does burn a little, which is why it slowly gets shorter (at the same speed as the candle gets shorter).
The wick in a candle is also mainly hydrocarbon with oxygen also present and this also burns though at a much slower rate. When you light the wick, you provide a heat source and oxygen from the air. The smoke formed contains carbon dioxide and water and also some soot from inefficient combustion.
When a candle burns, the wax does two things. First it melts, and then it burns. What burns is actually melted wax. The heat of the candle melts the nearby wax, and that melted wax is absorbed by the candle's wick. The melted wax burns on the wick -- the wick itself isn't burning, just the wax on it. However, as the candle burns down, what happens is there isn't enough wax nearby to melt, and so the end of the wick does burn a little, which is why it slowly gets shorter (at the same speed as the candle gets shorter).
It is a chemical change because there is new matter created but flammability is more of a property than a chemical change. A physical change is still the same matter but is in a different form like cutting paper. Its still paper. But if you burn paper, that’s a chemical change because it’s new matter now and it’s really hard to change back.
Butane example: 2 C4H10 + 13 O2 à 10 H2O + 8 CO2
A balanced equation for candle wax would be: C25H52 + 38 O2 à 26 H2O +50 CO2
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