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Alkynes do not react directly with aqueous acid as do alkenes, but will do so in the presence of mercury(II) sulfate as a Lewis acid catalyst. The reaction occurs with Markovnikov regiochemistry, so the OH group adds to the more highly substituted carbon and the H adds to the less highly substituted carbon. The initial product of the reaction is a vinyl alcohol, also called an enol. The enol immediately rearranges to a more stable ketone via tautomerization. Draw curved arrows to show the movement of electrons in this step of the mechanism

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Answer:

See explanation and image attached

Step-by-step explanation:

According to Markovnikov regiochemistry, the negative part of the addendum is joined to the more substituted carbon atom. The addition of H-OH to alkynes occurs in the presence of mercury(II) sulfate as a Lewis acid catalyst.

So, the -OH group is added to the highly substituted carbon and the H adds to the less highly substituted carbon.

The enol produced is shown in the mechanism attached to this answer. Rearrangement of this enol form due to keto-enol tautomerism yields the ketone as shown.

Image credit: chemistry steps

Alkynes do not react directly with aqueous acid as do alkenes, but will do so in the-example-1
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