[hamdani yusuf (OP)]

I found a spillage of sulfonic acid moving strangely. Does anyone know what caused it?
The spillage keeps moving like this for quite a long time, but eventually fading. When the movement stops, it becomes more viscous, but not completely dry yet.

[RD]

I found a spillage of sulfonic acid moving strangely. Does anyone know what caused it?

If it's moving of its own accord, could be due to heating to near-boiling via an exothermic reaction.

The changes in hue reminded me of those oscillating chemical reactions ...

[ That one also includes sulfuric acid ]