Molecule Orbital Electron Configuration?

Question

Which of the following is the molecular orbital electron configuration for 02 ^ 2- ?

A. (σ1s)2 (σ1s*)2 (σ2s)2 (σ2s*)2 (σ2p)2 (∏2p)6 (σ2p*)2

B. (σ1s)2 (σ1s*)2 (σ2s)2 (σ2s*)2 (σ2p)2 (∏2p)4 (σ2p*)4

Pls, not only answer,clear explanations...thanx :)

Sorry, Stacey...it's not "neither"
This was one of our mid-term quest..and i got it wrong. which the answer confused me with these 2 answer. The answer is B, bu i do not know why? Let's see other people's answers....HELP pls...

Answer 1

Neither!!!!!!!!!

I'm sorry to hear that your professor gave you a wrong answer to pick on your test. I am a chemistry PhD student...I think I know the answer. Look at b-----how are you going to hold 4 electrons in the sigma 2p* orbital since it has a maximum capacity of two??? If you do not belive me look at your sigma 1s* and 2s* orbitals. What, does the sigma 2p* orbital suddenly have the magical ability to hold four electrons????????????Not to mention that the sigma* orbital is lower in energy than the pi* one in B. In proper questions and answers it is the other way around. If you don't believe me why don't you try a good old fashioned textbook!

Assuming you did a typo and the last orbital in B is supposed to be Pi, then the answer is B. If not ....NEITHER!!!!!!!!!!!!!!

Look, also, at the link that the other answerer gave. Study the MO diagram and observe that the pi* comes before the sigma*.

I should change my user name to stupidity pisses me off.

Answer 2

It helps people pass chemistry exams. Apart from this, it is mostly an academic concept. It won't have any practical applications until the "two body" equation is solved. Schrodinger and several other physical chemists developed quantum mechanics, which described the behaviour of electrons in atomic orbitals. Their equations are exact only for Hydrogen atoms with a single electron. When another electron is introduced, the energy is impossible to calculate because of the interactions of the two electrons. Electrons are responsible for bonding between atoms. Bond strength can only be determined experimentally because it can't be calculated by hand. If the two body equation were solved then it would be possible to perform chemical engineering on paper and it would not be guesswork anymore. This would revolutionize technology. Room temperature superconducting materials would allow nuclear fusion reactors to become feasible and this would end the use of fossil fuel. The sorts of electro magnetic fields which could be generated might allow for the creation of things such as hover cars. Solving the two body equation would open a new age of technology seen these days only in science fiction.

Answer 3

The answer is B.

Here the easiest way to think of this:

Count electrons. Let's start with just dioxygen or O2. Oxygen is atomic number 8 so O2 has 16 electrons (i.e. 8 x 2 = 16).

But our molecule has a 2- CHARGE so that two more electrons! So we are at a total of 18 electrons!

So we start filling in our MO diagram. If you don't know for sure what a MO diagram for O2 looks like, see the website below.

The 2p orbitals of the two oxygen atoms when bound together are hybridized so the ∏2p can only "fit" 4 electrons. The next level is σ2p* and so you fill the last four electrons in this orbital.

I would highly recommend that you read this website on HOW to construct MO diagrams because they are different for different molecules.

Good Luck!

Answer 4

B: Look at the last 3 orbitals. In "A" You have a (sigma p2) and a (pi2p)6 . That's too many electrons in the three "p" orbitals. Only six electrons (total) can fit into the "p" orbitals just as in "regular" orbital theory and choice "A" has 8. (We're not looking at the "antibonding" p's, just the bonding p's).

Answer 5

Yeah, the answer is neither but that's only because the last orbital in b is not pi.