Question

what happen when ethyne gas is passed through red hot iron tube?

Answer 1

When ethyne gas is passed through red hot iron tube, benzene (C6H6) is formed.
Benzene is formed by the polymerisation of ethylene.
Three molecules of ethyne combines to give one molecule of benzene.

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Answer 2

Answer: It results in the formation of a cyclic compound named as benzene.

Explanation:

When ethyne gas is passed through red hot iron tube, it results in the formation of cyclic aromatic compound.

Three molecules of ethyne gas undergo cyclic polymerization to produce benzene.

The reaction for this reaction if given below in the image attached.