Question

Draw the electron-dot structure for ethyne. A mixture of ethyne and oxygen is burnt for welding. In your opinion, why cannot we use a mixture of ethyne and air for this purpose?

Answer 1

Ethyne burns in air with a sooty flame because of incomplete combustion caused by the limited supply of air.

However, ethyne burns in oxygen with a clean flame with a temperature of 3000°C because of complete combustion.

This oxy-acetylene flame is used for welding.

Such a high temperature cannot be achieved without mixing oxygen.

Therefore, a mixture of ethyne and air is not used for welding.