Oh Noes! Not Dihydrogen Monoxide!

[Urban Ranger]

Originally posted by Kucinich
CaO isn't a molecule. Molecules are formed with COVALENT bonds only.

That is so wrong I can't even tell you how wrong you are.

[Kuciwalker]

Hmmm, my textbook and my teacher say it is correct. UR, who has no chemistry credentials that I know of, says "it's wrong". Who do you think I should trust?

[Urban Ranger]

In chemistry, the molecule is the smallest indivisible portion of a pure compound that retains a set of unique chemical and physical properties.

Check the link in my previous post.

What do you call CaO? A couple of atoms just love to huddle together?

[Kuciwalker]

An ion.

[Theben]

ions can be molecules or atoms. They just have a + or - charge.

[Ogie Oglethorpe]

Kucinich,

CaO - Calcium Oxide is definitely a molecule. The fact that it is an ionic bonded molecule has no bearing other than to describe the type of molecule it is.

If you are inferring that b/c it is ionically bonded it can form ions in dyhydrogen monoxide, that may be true but has no bearing on the fact that this particular salt is indeed a molecule.

If your teacher has issue with this have him or her give me a shout. I think perhaps somethingisgettinglost in translation.

[Combat Ingrid]

Salts are not molecules. A molecule is defined by having covalent bonds.

[Ogie Oglethorpe]

CI,

Since when?

Salts most definitely are molecules. Do a simple search on Ionically bonded molecules.

Matter of fact there is a whole branch of chemistry associated with Inorganic Chemistry that speaks to molecules not having covalent bonds.

Believe me I've been doing this stuff 17 + years.

[Combat Ingrid]

From what I have learned salts are not molecules. A good example of the difference is to compare NaCl (a salt) with sucrose (a molecule). If you dissolve sucrose in water, you will get sucrose molecules dissolved in water. When you dissolve NaCl, you will not get dissolved NaCl molecules, but rather their ionic components dissolved in water.

However, I guess that compounds with stronger ionic bonds may be regarded as molecules. There's probably a grey area where you could define a given compound as both a "salt" or as a "molecule", depending on your taste

If you have been doing science for a long time, I assume you too know that one should be very careful with phrases like "most definitely"

[Ogie Oglethorpe]

CI,

The property of dissociation of ionically bonded molecules in dihydogen monoxide does not change the fact that there are three forms of molecular bonding.

Ionic, covalent, and polar covalent bonding. (Most folk do not recognize hydrogen bonding a chemical bond but some add that one in as a fourth).

[SpencerH]

CaO calcium oxide
CO carbon monoxide

Traditional nomenclature varies

Molecules do not have to be covalently bonded; consider the case of multimeric enzymes.

[Combat Ingrid]

But they are separate molecules held together by various non-covalent interactions.
Or do you suggest that the lipid bilayer (the cell membrane) is one single molecule?

I don't really want to discuss this further, it's all just a matter of definitions anyway. Since definitions are made by people they will never fully comply with reality

[-Jrabbit]

Nice threadjack!!

[MrBaggins]

Oh no! The sky is falling! The sky is falling!

or... at the very least solid Dihydrogen Monoxide crystals.

[SpencerH]

Originally posted by Combat Ingrid
But they are separate molecules held together by various non-covalent interactions.
Or do you suggest that the lipid bilayer (the cell membrane) is one single molecule?

I don't really want to discuss this further, it's all just a matter of definitions anyway. Since definitions are made by people they will never fully comply with reality

It is just a matter of definitions. Multimeric enzymes are called 'molecules' despite their being made up of smaller non-covalently linked molecules.