[Cryptocatron-11]

Hello, I'm french and i'm very bad in english.

I have a small question rather physicochemical. I wonder how the act of creating a potential difference can create a new bond between atoms.

Take a lisaison O-H. Hydrogen is stable, its potential energy is the lowest possible. I compare a nitrogen atom of the OH bond. It will cause an increase in the potential energy of the hydrogen which tend to the energy of dissociation. but the more we bring closer the particle N and the more the work required to break the OH bond becomes weak.

But even if the work tends to zero when approaching N, it always need a work and no matter how small it is. So the act of creating a field does not suffice to create the bond N-H We are thus obliged to add a little work . doesn't it?

Scuze me for my bad english.

[Arkcon]

If I understand correctly, you're asking how an existing stable bond can be replaced by another.  You give the example of a stable O-H bond and a N atom, but I could give an easier example:  stable H₂ gas and stable O₂ gas.  It requires some energy to combine these, that's true.  You seem to be asking why, if it requires energy, does it happen at all.  Well, sometimes, there is some energy around, say an electric spark for the reaction of H2 and O2, in my example.  Can you see how this is true.  Does this answer your question?

[Cryptocatron-11]

Not exactly. I know that reaction need some energy to be activate . My question is : is it enough to induce a field whithout work(work = variation of cinetic energy) for breaking a bound ? You can induce a field when you bring nearer an electronegative atom for example.

[fledarmus]

My question is : is it enough to induce a field whithout work(work = variation of cinetic energy) for breaking a bound ? You can induce a field when you bring nearer an electronegative atom for example.

Bringing atoms together does involve work - masses (albeit very small masses) are being moved over distances (albeit very small distances). If the two masses are oppositely charged, the driving force is the attractive force between them; if they are both neutral, the driving force is typically the kinetic energy of the masses in terms of their current velocity. That is why so much of the chemical mechanism discussion revolves around collisions between molecules.