# Is Elemental Sulfur a Lewis Acid or Lewis Base?

Is pure sulfur a Lewis base or a Lewis acid?

I am aware of the general concept behind what a Lewis base is (electron donor) and Lewis acid (electron acceptor).

This await on confuses me because I thought elemental sulfur could be either depending on the context in which it is found( I.e. What specific molecule it's found in)

I'm not sure if it is a Lewis acid or base when in elemental form.

Heat sulfur under hydrogen to form $\ce{H2S}$, and it's a Lewis base.
Heat sulfur under oxygen to form $\ce{SO2}$, and it's a Lewis acid.