A mixture of oxygen and ethyne is burnt for welding. Can you tell why a mixture of ethyne and air is not used?

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Chapter 4

NCERT

Class 10

Science

Solutions

2. A mixture of oxygen and ethyne is burnt for welding. Can you tell why a mixture of ethyne and air is not used?

Question:

A mixture of oxygen and ethyne is burnt for welding. Can you tell why a mixture of ethyne and air is not used?

Answer:

When ethyne is burnt in air, it gives a sooty flame due to incomplete combustion in limited supply of air. But, if ethyne is burnt with oxygen only, a clean flame with temperature above 3000°C is obtained because of complete combustion. Such flame is used for welding. It is impossible to attain such a high temperature without mixing oxygen. This is the reason why a mixture of ethyne and air is not used.

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