The product(s) obtained via oxymercuration  $\left({\mathrm{HgSO}}_4+{\mathrm{H}}_2{\mathrm{SO}}_4\right)$ of 1-butyne would be

${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{C}\equiv \mathrm{CH}\frac{{\mathrm{HgSO}}_4{\mathrm{H}}_2{\mathrm{SO}}_4}{2\mathrm{H}\cdot \mathrm{O}}{\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{C}(\mathrm{OH}{)}_2{\mathrm{CH}}_3\stackrel{-{\mathrm{H}}_2\mathrm{O}}{\to }{\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CCH}}_3$

1-butyne reacts with mercurous sulphide and sulfuric acid to produce isobutyl alcohol, which then passes through tautomerism to produce ethyl methyl ketone.