Question

Goldsmiths blow the outermost zone of flame with a blow-pipe for melting gold and silver. Why do they use the outermost zone?

(1) It is the zone of incomplete combustion and is least hot.

(2) It is the zone of complete combustion and is the hottest zone.

(3) It is the least hot zone and complete combustion takes place in this zone.

(4) It is the hottest zone though incomplete combustion takes place in this zone.


choose the correct option ​

Answer 1

Answer-(2) It is the zone of complete combustion and is the hottest zone.

Explanation:

Goldsmith- Goldsmiths blow the outermost zone of a flame with a metallic blow pipe for melting gold and silver. ... The melting point of gold and silver is very high therfore goldsmiths need maximum temperature. Hence goldsmith use outermost part of the flame because it is the hottest part of flame.