Valence electron configurations

[Edris Saadat 1A]

On quiz 2 preparation(2014) questions 6 and 7 ask to find the valence electron configuration of molecular chlorine and He₂. How exactly do we solve this? Must we do the lewis structure, find the correct shape, and then place sigma/pi bonds? Or do we place the sigma/pi bonds in their respective energy levels?

[JK Suh 3C]

Do we even need to know this for the quiz this week? I'm like 73% sure we don't... Can anyone verify?

[Edris Saadat 1A]

Im not sure. What about paramagnetic and diamagentic molecules, bond order, and the Molecular Orbital Theory?

[404651793]

I am having trouble doing the valence electron configurations for any molecule. I The question is to "write out the valence electron configuration for molecular chlorine." This is difficult because I do not know where to write the sigma and pi bonds or what numbers to place in front or if I write sp or just s or just p for the orbitals.

[chemgal4L]

All you do is count the electrons in the specific orbitals. So for Chlorine for example, you see that the firs ts orbital (the top two squares on the periodic table are filled) so you have 1s2, then you see that the second s orbital (Li and Be) is also filled, so you have 2s2, and the 2p orbital is filled as well with 6 possible electrons, 2p6, same with 3s, 3s2, and lastly you only have 5 electrons in the 3p orbital, so 3p5. So the electron configuration for chlorine would be: 1s2 2s2 2p6 3s2 3p5, or [Ne] 3s2 3p5