Complete the mechanism for the formation of the major species at equilibrium for the reaction of butanal in methanol solvent and catalytic aqueous acid. Make sure to include any missing atoms, bonds, charges, nonbonding electrons, and curved arrows. Then classify the final product below.

Select the choice that best describes the final structure.

0 H -0 H H * H8H H 1L 1L H "H H 1L H H FO 0-H H H :0 28-4 H oooo 1 gem-diol gem-diol 2 hemiacetal O acetal