[UG]

How can I tell what the products are of these reactions? I cannot find anything about this in my books, only information on primary amines.  Are the products of 2^o and 3^o amines the same as primary amines?
Anyway, here are the questions:

(CH₃CH₂)₂NH + H₂SO₄ 

(CH₃CH₂)₃N + HNO₃ 

Is this correct?

2(CH₃CH₂)₂NH + H₂SO₄  2(CH₃CH₂)₂NH₂⁺ + SO₄^2- OR is it written: ((CH₃CH₂)₂NH₂⁺)₂(SO₄^2-)

(CH₃CH₂)₃N + HNO₃  (CH₃CH₂)₃NH⁺ + NO₃^- OR is it written: ((CH₃CH₂)₃NH⁺)(NO₃^-)

How do I name the products?

[azmanam]

While sulfuric acid is a diprotic acid, it will only react once with the amine.  The stoichiometry is 1:1.

They are all ammonium salts, so you'll name the organic cation as an alkylated ammonium species.  Do you know what the anions would be called?

[UG]

Hydrogen sulfate and nitrate?

-----

So the first reaction should be?

(CH₃CH₂)₂NH + H₂SO₄  (CH₃CH₂)₂NH₂⁺ + HSO₄^-

[UG]

While sulfuric acid is a diprotic acid, it will only react once with the amine.  The stoichiometry is 1:1.

In one of my books the reaction between aminomethane went as follows:

2CH₃NH₂ + H₂SO₄  (CH₃NH₃⁺)₂(SO₄^2-)

Is this incorrect? Or are they assuming that there is excess sulfuric acid? 

[azmanam]

Well, here's my thought process.  Acid base reactions are always equilibria, and the mnemonic says Weaker Acid Wins.  First reaction is sulfuric acid with the secondary amine.  pKa -3 vs 11, protonated amine wins, with the bisulfate as the byproduct.  From here on out, there are choices.  By sheer numbers, there is an abundance of secondary amine and sulfuric acid - so most reactions will be amine with sulfuric acid again.  But of course amine could react with bisulfate.  pKa of bisulfate is around 2, so 2 vs 11, protonated amine wins again, giving the sulfate dianion and 2 protonated amines.  BUT, unless stoichiometry is carefully controlled, some sulfuric acid will approach the sulfate dianion.  That's an interesting situation.  pKa of sulfuric acid is -3 and the bisulfate anion is around 2.  so if the dianion does form, it will be protonated by sulfuric acid giving 2 bisulfate anions and the protonated amine in the 1:1 ratio.  See attached.

[UG]

Thanks! 
I didn't know that the last reaction between the bisulfate anion and sulfuric acid could happen 

[Borek]

I didn't know that the last reaction between the bisulfate anion and sulfuric acid could happen 

It happens all the time.

It all depends on the stoichiometry. As long as there is more sulfuric acid than amine (in terms of molar ratio), you will get bisulfate. But if the ratio is below 1 (say 0.75 mole of sulfuric acid and 1 mole of amine) you will get some sulfate. This is simple stoichiometry.

[UG]

Can I just ask something else while we're on amines. A haloalkane is reacted with ammonia dissolved in alcohol to produce an amine, why must the solvent used for the reaction be alcohol and not water?
Is it to stop this from happening? NH₃ + H₂O  NH₄⁺ + OH^-
If not, why?

[Borek]

Won't water compete with ammonia?

But don't treat me too seriously, my knowledge about organic chemistry is almost nonexistent.

[UG]

Haha, no worries.
Don't be too hard on yourself  If your knowledge of organic chemistry is almost non-existent then I'm doomed! DOOMED I tell you!   
Anyway, I can wait for someone who has an answer.

[Dan]

Since the pKas of water and alcohols are not wildly different, I don't think the acid/base reaction is the problem. In an Sn2 reaction water is unlikely to compete with ammonia as a nucleophile. Could it be simply that an effective solvent must dissolve the reagents, and a simple haloalkane is not going to be very water soluble?

[azmanam]

It's also important to note that reaction of ammonia with a halo alkane will not stop at one substitution - even if the stoichiometry is 1:1.  Alkyl groups make the amine more nucleophilic and the result will be a quaternary ammonium salt.  This is not a good way to make primary amines, fyi.

[UG]

Thanks, now I just got to find out what my teacher says.