Question

Question number 16 pls I will mark as brainliest answer

Answer 1

Answer:

because in air other compounds are also present so mixture of air and ethyne is not used for welding

Answer 2

Answer

The mixture of ethyne and oxygen is burnt for welding because the reaction is highly exothermic and the product is singer molten state.

but the mixture of ethyne and air is not used because air is a mixture of many gases including nitrogen in a high content . So this will reduce the heat generated