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Chemistry · PYQ NEET UG 2019(2)
हिन्दीIn the following reaction, \( \text{H}_3\text{C}-\text{C}\equiv\text{CH} \xrightarrow[873\text{ K}]{\text{red hot iron tube}} \text{A} \). The number of sigma \( (\sigma) \) bonds present in the product A, is
Correct answer · Option 2
21
Explanation
Propyne on cyclic trimerization gives mesitylene (1,3,5-trimethylbenzene), whose molecular formula is \( \text{C}_9\text{H}_{12} \). Total \( \sigma \) bonds = \( 9 (\text{C-C}) + 12 (\text{C-H}) = 21 \).
