Question

a wax candle burns with a yellow flame the domestic gas burns with a blue flame why

Answer 1

The gas flame appears blue because complete combustion creates enough energy to excite and ionize the gasmolecules in the flame. With complete combustion, an LPG (Propane) flame burns at a temperature of around 1,980°C. For Natural Gas (Methane), the temperature is about 1,960°C.
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