[magdi_gamal]

I understand that the chemical equation would be...

 CH₃CH₂NH₃ Br + NH₃ ---> CH₃CH₂NH₂ + NH₄⁺ Br<sup>-


My confusion is that in this link it says the ammonia only takes a hydrogen ion from ethyl-ammonium bromide...

 http://www.chemguide.co.uk/organicprops/amines/preparation.html#top

But then if the fourth hydrogen in the NH4 is only a proton. then wouldn't have just enough electrons to fill its outer shell? So how would it give bromide the electron it needs?
So to summarize the question how does NH4Br form an ionic bond?</sup>

[Rutherford]

The ammonia removes a proton from ethyl-ammonium bromide. NH₄⁺ is produced so the negative bromide will bond to it (as it can't bond with the neutral ethylamine).

[magdi_gamal]

The ammonia removes a proton from ethyl-ammonium bromide. NH₄⁺ is produced so the negative bromide will bond to it (as it can't bond with the neutral ethylamine).

Thanks, but I'm still confused. how is the ethylamine in the products neutral if it had just lost a positively-charged particle? also, Why is the bromide negatively charged if it hadn't gain any electrons yet?

[Rutherford]

Maybe the more correct formula of the starting compound can help you:
 CH₃CH₂NH₃⁺Br^-
Understand now?