[Needaask]

Hi this is my first post on chemicalforums hope to get help from you guys

I am reading an organic chemistry book titled 'get ready for organic chemistry' and I read the chapter on acid base reactions. After learning about which anion would be more stable by checking 1) the atom the H is bonded to 2) number of resonance structures 3) inductive effects and 4) geometry, the book covered on reaction mechanism.

The book's reactions were these HA+B-  A- +HB
So in the practice question all the reactions are like the given equation. However, I'm not sure how do I apply what I learned in terms of how strong an acid is to other reactions.

For example when NH3 reacts with water, looking at the atom hydrogen is bonded to, water is more acidic than ammonia as the hydrogen is bonded to oxygen which is more electronegative than nitrogen. So would that the thought process be like, such that the ammonia takes the hydrogen from water and the bond pair in the O-H goes to the oxygen producing NH4+ and OH-. But from my past education, I sort of already know that those will be the products of this reaction.

But when I try to draw the mechanism of NH3+Na2CO3 so in this case, my thought process would be that ammonia is more acidic as the Na2CO3 does not have any hydrogens at all. So the oxygen on the carbonate ion will take the hydrogen from ammonia producing NH₂^- and NaHCO3.

Would my thought process be correct here?

Thanks so much for the help in advance

[Hunter2]

Amide NH₂^- is not stable in aqueous solutions. In water you will find NH₄⁺ , CO₃^2-, HCO₃^-, OH^- and Na⁺.

[Needaask]

Amide NH₂^- is not stable in aqueous solutions. In water you will find NH₄⁺ , CO₃^2-, HCO₃^-, OH^- and Na⁺.

Hi Hunter2 thanks for the reply.

Hmm, I'm having a lot of trouble understanding the mechanism in these reactions. For example, when NH₄⁺ reacts with OH^- from my book I assume that the more acidic substance will force the less acidic substance to act as a base and the way to determine which substance is more acidic is to look at which atom the hydrogen atom is bonded too (that is the most important factor for acidity in my book), so looking at the 2 substances, oxygen being more electronegative than nitrogen I would guess that the OH^- ion is more acidic than the NH₄⁺ ion. But that's not true as in this acid base reaction NH₄⁺ gives up its proton to the OH^- to form ammonia and water. So what's wrong with my concept?

Also, I'm not very sure what to do if the spectator ions were given to me. In the ammonium and hydroxide ion case, if the spectator ions were given I would be able to tell they they would get cancelled out in the products due to my secondary school education. However, I was told that in higher levels of education I should use the mechanism to deduce the products of my reaction. So in such reactions, how should i tell which are the spectator ions in a reaction?

I'm quite worried about this because it seems like I can't really understand the mechanisms in the acid-base reaction which according to the book should be very simple to understand..

Thanks so much for the help