Sulfate Ion

[Vincent Chiang 1L]

When you draw the sulfate ion (SO4)^2-, how can the sulfur share six electrons and have a total of 12? I thought the max was 8... Thanks in advance.

[Tanaisha Italia 1B]

This is an anion and thus the compound has gained two more electrons. Suphur has 6 valence electrons, plus is sharing 6 electrons with oxygen. Therefore, the total is 12. Sulphur has two single bonds and two double bonds distributed between the 4 oxygen atoms. since each single bond shares 2 electrons and each double shares 4, this equals 12 in total.

[Annalise Eder 2L]

Sulfur can have an expanded octet by using the empty 3d orbitals to accommodate "extra" electrons.

[Peri Bingham 1G]

Atoms in period 3 or higher, like sulfur, can have more than 8 valence electrons because they can occupy the d-orbitals.

[Curtis Tam 1J]

If you were to calculate the formal charge of the sulfur in this Lewis structure, you would get a formal charge of 0, which is favorable.