| MadSci Network: Chemistry |
What you are looking for is the quantity known as the Heat of Combustion. These values can be found in many reference books. I used the CRC Handbook of Chemistry and Physics for this answer. It also helps to know that a candle is made of wax and that the correct chemical name for wax is paraffin. With that, we find a value of 10.340 Kg-calories per gram of paraffin. Of course this is valid only if you actually burn the candle. Eating the candle will produce no calories because wax is indigestable.
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