What product is formed when ethene reacts with bromine?

When ethene (C2H4) reacts with bromine (Br2), the product formed is 1,2-dibromoethane (C2H4Br2). Here's the step by step process:

1. Ethene is an alkene, which means it has a carbon-carbon double bond.

2. Bromine is a halogen, and it can add across the double bond of alkenes in a reaction known as a halogen addition reaction.

3. In this reaction, the bromine molecule is polarized by the high electron density of the double bond of the ethene molecule. This causes the bromine molecule to become a bromonium ion (Br+) and a bromide ion (Br-).

4. The bromonium ion (Br+) then reacts with the double bond of the ethene molecule, opening the double bond and attaching to the carbons.

5. Finally, the bromide ion (Br-) attacks the bromonium ion, leading to the formation of 1,2-dibromoethane.

So, the product of the reaction between ethene and bromine is 1,2-dibromoethane.