Oh Noes! Not Dihydrogen Monoxide!

[Combat Ingrid]

So you didn't think carefully, Centrifuge

A NaCl crystal does not contain NaCl molecules. It's simply a grid of Na+ and Cl- ions.

Check your textbook in inorganic chemistry if you don't believe me

[centrifuge]

You guys are going to force me to start digging out all of my old textbooks aren't you

[Combat Ingrid]

Yes

[Az]

CI

when you have a NaCl Crystal, you cannot differentiate between. different molecules.

Try to imagine an organic molecular crystal on the atomic level. It's obvious you'll be able to differentiate between molecules.

[Provost Harrison]

Originally posted by Azazel
At my Atkins general chemistry book, I remember very clearly they said that it's NOT a molecule. I was shocked, btw.

Provost, this is true. I think that the nature of the Na-Cl bond is around 90% Ionic, and the rest is covalent.

I think the question we must ask is, can we evaporate NaCl, and bring it to a state where small particles of NaCl float?

Oh I agree, NaCl is definitely ionic and forms a lattice. In reality there is no such thing as an NaCl unit as it forms a lattice - NaCl is it's empirical formula in effect. But there is a lot of grey area in this definition though. CsF would most definitely be ionic, and O2 would certainly be covalent, but what would, for example, AgBr be?

[Az]

[centrifuge]

Originally posted by Combat Ingrid
So you didn't think carefully, Centrifuge

A NaCl crystal does not contain NaCl molecules. It's simply a grid of Na+ and Cl- ions.

Check your textbook in inorganic chemistry if you don't believe me

Yes, yes, yes, but the point is that you can take 1 Na+ and 1 Cl- and have a compound which has all of the same properties of the bulk crystal,

...which by every definition that I've seen, makes it a molecule.

[Az]

Oh I agree, NaCl is definitely ionic and forms a lattice. In reality there is no such thing as an NaCl unit as it forms a lattice - NaCl is it's empirical formula in effect. But there is a lot of grey area in this definition though. CsF would most definitely be ionic, and O2 would certainly be covalent, but what would, for example, AgBr be?

Well, noone said the world is black and white. You can also have complexes forming. that make you ask "is this a molecule"?

BH3-O(Me)2., for example.

[Combat Ingrid]

Originally posted by centrifuge
Yes, yes, yes, but the point is that you can take 1 Na+ and 1 Cl- and have a compound which has all of the same properties of the bulk crystal,

...which by every definition that I've seen, makes it a molecule.

No, the point is that the NaCl "molecule" is mainly theoretical in nature

[centrifuge]

Originally posted by Combat Ingrid


No, the point is that the NaCl "molecule" is mainly theoretical in nature

Okay, I'll agree with that,

...but truthfully a great deal of chemistry relies upon modeling things in ways that are not seen in nature.

[Combat Ingrid]

True

[Provost Harrison]

Modelling for the purposes of calculation only...stoichiometric calculations would be murder otherwise But you have to keep an image of the broader picture in your mind about what is going on.

[Az]

what's REALLY going on, that is.

[centrifuge]

Originally posted by Provost Harrison
Modelling for the purposes of calculation only...stoichiometric calculations would be murder otherwise But you have to keep an image of the broader picture in your mind about what is going on.

Somewhere in the middle of graduate school, I decide to stop giving a **** about what was really going on

...that's sometimes the problem I think, as you become more and more specialized you can sometimes bypass the little details on areas that aren't related to your specialty.

[Az]

what's your specialization, centrifuge?