There is no known stable compound with the name "sulfur tetroxide". Here's why:

* Sulfur's Valency: Sulfur typically forms compounds with a maximum valency of six (meaning it can form up to six bonds).

* Oxygen's Valency: Oxygen typically forms two bonds.

* Formula: A compound named "sulfur tetroxide" would have the formula SO₄. However, this formula indicates that sulfur would have to form eight bonds (four with oxygen atoms), which is not possible.

The most common and stable sulfur oxide is sulfur dioxide (SO₂). In this compound, sulfur forms two double bonds with oxygen.

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