# NH3+-CH(CH3)-COO- Zwitterions

Hi, i'm wondering how zwitterions works? For example, alanine.

NH3+-CH(CH3)-COO-

This is when it is in a neutral form right? But my teacher taught me that, when you add it into a alkali or acid solution. Let's take alkali for instance, the OH- reacts with the NH3+. But by my knowledge, OH- would mean a basic solution and NH3+ is a base. How could a base react with a base?

Thanks for the reply. I'm clear now. So when alanine is in solid form, will it have the zwitterion form? the NH3+ end and COO- end? Or does this only occur in water/acid/alkali ?

Borek
Mentor

I doubt it will be strictly zwitterion. However, without knowing exact crystallic structure it can be difficult to predict what is going on in the solid. Seems logical that hydrogen bonding between COOH and NH2 plays some role in the crystal structure.