Hydration of alkynes (adding \(H_2O\) with \(Hg^{2+}/H^+\)) is a key reaction.
- For terminal alkynes (except acetylene), it follows Markovnikov's rule and always produces a methyl ketone.
- For symmetrical internal alkynes, it gives a single ketone.
- For unsymmetrical internal alkynes, it gives a mixture of two ketones.