So4 -2 — Lewis

In the bustling molecular city of , there lived a famous central figure named Sulfur . Sulfur was a bit of an overachiever. While his neighbors, like Oxygen and Hydrogen, were happy with simple bonds, Sulfur wanted to connect with everyone.

To the other two Oxygens, he gave single bonds but with a heavy heart: "You will carry the negative charge for the team." so4 -2 lewis

But there was a problem. When Sulfur tried to share a single pair of electrons with each Oxygen (making four single bonds), he ran out of electrons. He was left with a miserable +4 formal charge, and each Oxygen had a -1 charge. The structure was unstable, like a table with three legs. In the bustling molecular city of , there

One day, Sulfur decided to host the biggest gathering in the valley. He sent invitations to four Oxygen atoms. To the other two Oxygens, he gave single

In reality, all four Sulfur-Oxygen bonds were —a perfect average between a single and a double bond (called a bond order of 1.5). The negative charge was spread evenly across all four Oxygens.

He summoned two of the Oxygen atoms. "You two," he said, "will share double bonds with me."

Every millisecond, the double bonds would hop from one Oxygen to another. Click. Now a different Oxygen has the double bond. Click. Now another.