The colour of the outermost zone of a candle flame is _________.
The outermost zone of a candle flame is blue in colour. It is also called non-luminous zone where the complete combustion of wax takes place.
The colour of outer zone of a candle flame is ___.
In a candle flame, what is the colour of : (a) innermost zone (b) middle zone, and (c) outer zone ?