Thread: Basic particle physics

My question relates to ions and the way they are explained in a particular text book I have.

The definition of an ion is an electrically charged particle. I know I'm splitting hairs here, but if you were being technical, wouldn't you say that the definition is an "electromagnetically" charged particle? Isn't it the magnetic force that creates the attraction between converse charges?

Next, let's say that I have an atom of Na+ (or an Na+ ion) and an atom of Cl- (or Cl- ion), my text says that when they come together, they "ionize" each other. When something is ionized it either gains or loses an electron and this is in fact what happens, so is it correct to say that the ions have ionized one another? Something doesn't seem right about that, so I thought I would ask. Maybe my premise is incorrect and those elements do not start off as ions in the first place but instead become ions after bonding...?

Thanks!

MM

I know this in terms of chemistry.

The Na radical is an unstable atom because it has one orbital with one single electron, so is the Cl atom. When two atoms like this get close to each other they tend to form a covalent bond, which means that they each donate one electron for the bond and reach a stable state this way. In the case of Na and Cl however the difference in electronegativity is higher than 2,0, with the Cl being the more EN atom. This means that Cl attracts the two electrons of the bond so much that it just takes them both.

That leaves the Cl with an excess negative charge and the Na with on less negative, or one excess positive charge.

Hmmm...I think you might be confusing the properties of NaCl with a hydrocarbon perhaps. NaCl is held together by an ionic bond which is when electrons are given/taken from one atom to another. In a covalent situation, the electron is shared by the two atoms; it spends time orbiting both nuclei.

The questions I have are:

1. Do Na and Cl start as ions and then ionize each other again when they come together?

2. Is it more correct to say that an ion is an "electromagnetically" charged particle?

Thanks!

MM

No I must have expressed myself wrong, you can think of an ionic bond as an covalent bond which is just absolutely polarised.

Ionization is electrical because it involves discrete charges. Ionization mostly proceeds with removal of electrons. Occ. the addition. These are discrete charges, -1, +2, and so forth. As an heavier element's atom becomes more ionized, electrons are sequentially stripped away. This is an electrical effect, not a magnetic effect. Certainly there are magnetic effects here, as current can be generated using the charge differential, esp. in MHD systems.

But ionization is electrical, NOT magnetic because it involves discrete electrical charges, and magnetic effects are not contributory.