Styrene (1.53 g, 0.011 mol) in methanol (30 mL) was added to a mixture of Hg(OAc)2 (5.30 g, 0.016 mol) in methanol (100 mL) at room temp. and stirred for 24 h. Sodium hydroxide (3.0 M, 16 mL) was added, followed by NaBH4 (0.32 g, 0.008 mol) in NaOH (3.0 M, 16 mL) at 0 °C. The precipitated Hg was removed by filtration. The product was isolated by diethyl ether extraction. After drying over Na2SO4, solvent was removed and distillation gave the product. (Adapted from: Senda, Y.; Kanto, H.; Itoh, H. J. Chem. Soc., Perkin Trans. 2 1997, 1143-1146.)

Styrene reacts in oxymercuration and demercuration in the present of methanol to form 1-methoxyethyl benzene.

Explanation:

See the attached file for the mechanism of reaction

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.