The colour of outer zone of a candle flame is ___.
The outer zone of candle flame is blue in colour. It is where the complete combustion takes place.
In a candle flame, what is the colour of : (a) innermost zone (b) middle zone, and (c) outer zone ?
Which zone of a candle flame is the hottest ?
Name the various zones of a candle flame. Which zone (or part) of a candle flame is the least hot (or coldest) ?