[juand.ro97]

Well I read in a book that an amide and a strong acid poduce an alkylammonium salt, so in the laboratory I made the following reactions:

Aniline + HCl and Aniline + Sulfuric Acid
(1) C6H5NH2 + HCl = C6H5NH3+Cl-
(2) C6H5NH2 + H2SO4 = (C6H5NH3+)2 SO4-2

Triethylamine + HCl and Triethylamine + H2SO4
(3) (C2H5)3N + HCl = (C2H5)3NH+Cl-
(4) (C2H5)3N + H2SO4 = ((C2H5)3NH+)2 SO4-2

So in the lab in reactions (1) and (2) it was obtained a gas and a yelowish solid, wich confuses me because there is only one product according to the equation. In (3) there was a lot of gas but no solid, and in (4) the reaction doesn't seem to happen at all. So if someone can explain me that I'd apreciate it.

Oh and I'm not completely sure the equations are correct because I made them myself based on an example.

[ATMyller]

Tertiary amines do not always bind H⁺ to the lone pair due steric hindrance from the other groups.

[Babcock_Hall]

Triethylammonium salts would be expected to be much more soluble in water than triethylamine, which is immiscible.  Therefore, I would not expect to see a solid unless I evaporated all of the water.

[juand.ro97]

Hi, would you mind telling me why triethylammonium salts are more soluble, I understand that all ammonium salts are ionic and therefore completely soluble in water.

[Babcock_Hall]

What intermolecular forces can a triethylammonium ion experience with water that triethylamine cannot?  I can think of two.

[juand.ro97]

Well a triethylammonium ion has an N-H bond so it can form hydrogen bonds with itself, wich triethylamine can't.

[Babcock_Hall]

Yes, and there is also an ion dipole force between the positive charge on the triethylammonium ion and water.

[juand.ro97]

But doesn't that apply to anilinium salts as well? They do form a solid

[Babcock_Hall]

Sulfuric acid has very little water, much less than hydrochloric acid, although I am not sure that this is the whole story (aniline is  rigid molecule, whereas triethylamine is not).  Did the product of aniline and HCl stay in solution or fall out as a solid.  I am not entirely clear from your first post.

[juand.ro97]

Yes, the aniline and HCl formed a solid, aniline and sulfuric acid also did. But none of the triethylamine formed a solid, I should've also said that it was with very little substance, like one drop of each reactive.