Why does the octet rule not hold for many compounds containing elements in the third row of the periodic table and beyond? (Select all that apply.)

1. Atoms of elements in the third period are less subject to destabilization from additional electron-electron repulsions.
2. Atoms of elements in the third period contain f orbitals that are relatively close in energy to 3p and 3d orbitals and provide an allowed energy state for extra electrons.
3. Atoms of elements in the third period have the space and available orbitals to accommodate extra electrons.
4. The third shell contains d orbitals that are relatively close in energy to 3s and 3p orbitals and provide an allowed energy state for extra electrons.

I put 1,3 1,2,3 3,2 and 4,1 1,2,3,4 just 1 just 2 just 3 just 4 but none of those combos worked!

You can read more about it here.

http://www.mikeblaber.org/oldwine/chm1045/notes/Bonding/Except/Bond08.htm

I would pick 3 and 4.

The correct answer is 2 and 4.

Explanation:
1. Atoms of elements in the third period are less subject to destabilization from additional electron-electron repulsions. This statement is not correct because electron-electron repulsions affect atoms in the third period in the same way as atoms in the second period.
2. Atoms of elements in the third period contain f orbitals that are relatively close in energy to 3p and 3d orbitals and provide an allowed energy state for extra electrons. This statement is correct. Elements in the third period and beyond have access to the f orbitals, which are closer in energy to 3p and 3d orbitals, allowing for more electron accommodation.
3. Atoms of elements in the third period have the space and available orbitals to accommodate extra electrons. This statement is not correct on its own. While elements in the third period have more available space and orbitals, it does not explain why the octet rule does not hold.
4. The third shell contains d orbitals that are relatively close in energy to 3s and 3p orbitals and provide an allowed energy state for extra electrons. This statement is correct. The presence of d orbitals allows for extra electron accommodation in elements in the third period and beyond.

Therefore, the correct selections are 2 and 4.

To determine why the octet rule does not hold for many compounds containing elements in the third row of the periodic table and beyond, let's evaluate each option:

1. Atoms of elements in the third period are less subject to destabilization from additional electron-electron repulsions.
This statement is correct. As we move across the periodic table, the atomic radius decreases, leading to higher electron-electron repulsions. Therefore, elements in the third period are less likely to adhere to the octet rule due to increased destabilization from additional electrons.

2. Atoms of elements in the third period contain f orbitals that are relatively close in energy to 3p and 3d orbitals and provide an allowed energy state for extra electrons.
This statement is incorrect. Elements in the third period do not contain f orbitals. The f orbitals come into play in the fourth period and beyond, not the third period.

3. Atoms of elements in the third period have the space and available orbitals to accommodate extra electrons.
This statement is correct. Atoms in the third period have additional orbitals, including the 3d orbitals, which expand the capacity for accommodating extra electrons beyond the octet rule.

4. The third shell contains d orbitals that are relatively close in energy to 3s and 3p orbitals and provide an allowed energy state for extra electrons.
This statement is correct. The presence of d orbitals in the third shell allows for additional energy states for electrons, which can facilitate the accommodation of extra electrons in compounds containing elements in the third period.

Therefore, the correct options are 1 and 3.