What happens when:
(i) Ethyl alcohol is heated in the presence of Al2O3 at 493 K?
(ii) Ethylene dibromide is heated with zinc dust?
Explain the mechanism of the following reaction:
Mechanism of the above reaction involves three steps:
(i) Formation of protonated alcohol. H2SO4 ionises to give H+ ion which attacks the molecule of alcohol to form protonated alcohol.
(ii) Formation of the carbocation. Protonated alcohol eliminates a molecule of water to give a carbocation.
(iii) Formation of ethylene. Carbocation finally loses a proton to hydrogen sulphate ion to form ethylene.
Discuss the mechanism of addition hydrogen acids to symmetrical alkenes. Justify the order of reactivity of halogen acids HI > HBr > HCl.