To complete the reaction, you need to add the products that are formed from the reaction between СН2=СН−НСО and Br2.

The products of this reaction are СН2=СН−НСОBr and HBr. This is because Br2 is a halogen and it will react with the alkene's double bond to form a halogenated compound.

Therefore, the full reaction is:

СН2=СН−НСО + Br2 → СН2=СН−НСОBr + HBr

As a chemist, it's important to always name the products of a reaction. In this case, the product СН2=СН−НСОBr is called bromoacrolein. The IUPAC name for HBr is hydrogen bromide.

Remember to always follow the proper naming conventions for organic compounds and inorganic acids when writing chemical equations. Happy naming!