[gregdwulet]

Hey everyone,

My teacher was going over bonding as a review in my AP chem class and I thought of something that it confusing me:

In, for example, the third energy level, the d orbitals are the ones of highest energy and are thus the last to be filled with electrons. Since these electrons are in the outermost shell, the would be considered valence electrons and are available for bonding. But elements in group 12, like Zinc and Cadmium, must then be unreactive, since they have filled outer orbitals? Would these elements be like the "Noble Gases" of transition metals?

It seems that they are too stable to bond since (as far as I know) they don't have very high ionization energies and would not want to become anions because doing so would add electrons to the next higher energy level and thus require a lot of energy inputted into the system...

[cliverlong]

Err ... well, yes, no , maybe  

I have re-read your post several times and just get the feeling it is a jumble of ideas thrown in a bag, shaken and they have come tumbling out. I'm not even sure what your question is.

What I do suggest is you read the following carefully

http://www.chemguide.co.uk/inorganic/transition/features.html

since I think it deals with the issues you wish to tackle.

Then rephrase your question.

For your teacher to claim that transition metals are unreactive (if I can extract that from your post) - is rubbish of the highest order. Somehow I don't think that is what he/she meant - I would be worried if he / she did. A simple example is that iron rusts.

Clive

[cth]

Zinc (and cadmium) can easily loose two electrons from its 4s (and 5s) orbital to become Zn²⁺ (and Cd²⁺). Then, their 3d orbitals are full. They are stable in this state.

They would be unreactive like noble gases if they were electrically neutral... But, they carry a +2 electric charge. So, anything negatively charged or with lone electron pairs can be attracted and coordinated to Zn²⁺ and Cd²⁺. Those coordinations are purely electrostatic interactions and the d orbitals are not involved. Strictly speaking, one should not talk of "coordination bond" in this case. It is similar to Na⁺ attracting Cl^- by ionic forces only.