When 1-butene undergoes hydration in the presence of H2SO4 and H2O, the major product formed is 2-butanol. This reaction follows Markovnikov's rule, where the hydrogen atom from the water molecule adds to the carbon with more hydrogen atoms, and the hydroxyl group OH adds to the carbon with fewer hydrogen atoms. In this case, the hydrogen will add to the terminal carbon, and the hydroxyl group will add to the internal carbon, resulting in the formation of 2-butanol.