Rxn Mechanism for Acid Catalyzed Electrophilic Addition

[Joslyn_Santana_2B]

Step 1: Where is Hydrogen that broke off from the H30? I thought the double bond was attacking it, causing it to break off.

Step 2: How are there 2 H20 molecules? How is there a product of H+/H30+?

[Chem_Mod]

Step 1: Where is Hydrogen that broke off from the H30? I thought the double bond was attacking it, causing it to break off.

Step 2: How are there 2 H20 molecules? How is there a product of H+/H30+?

1. The hydrogen from hydronium adds to one side of the double bond. The carbocation is formed on the other side.

2. The reaction is in water. There are probably a million times more water molecules relative to the reactants. H⁺ is not a real thing. Hydronium (H₃O⁺) is regenerated, hence the name acid catalyzed.

Also, the mechanism is incorrect. The second step is trying to combine two elementary steps into one. The steps would occur as depicted below. What is shown is a termolecular reaction (three things reacting at the same time). This will almost never happen.