Question

Which zone of a flame is used by a goldsmith to melt gold or silver and why?(b) Your grandmother wants to make kajal (black charcoal), which part of flame help her to doso?(c) Why does the wick of a candle not burn?(d) Why the wax in and near the wick of a candle melts?

Answer 1

a)Agoldsmith uses the outermost zone of the flame for melting gold and silver as this part is the hottest part of a flame 
b) the lower part of flame that produces soot in sufficient qnty can be used for making kajal at home.
c).  the wick of the candle works by capillary action , it draws molten candle wax up to the flame which vaporises at the wick and burns , so wick does not burn but it is the melted wax that burns 
d) wax n and near the wick burns due to the heeat produced by burning of already molten wax.

Answer 2

non luminous or outer zone in the zone of complete combustion and also the hottest part of the candle flame is used by goldsmith for melting gold and silver