When a Candle Burns, Where Does the Wax Go?

The wax does not disappear into the glass, and it does not mostly evaporate onto your ceiling. It melts into a pool, the wick draws it up, the heat turns it into vapour, and the vapour burns. The missing centimetres became the flame, a bit of water, a bit of carbon dioxide, and a little soot if you were sloppy with the wick.

What you should be left with

A centimetre you chose not to burn, so the tab would not overheat. A bit of scent in the room. Maybe a faint film on the lid. If you have a thick wall of unused wax, that wax did not “go” anywhere — you tunnelled it. Fix the tunnel or live with a wasted ring.

Soy-coconut burns cleaner than a sooty paraffin in a draught, which is not the same as “smoke free”. Trim. Still air. Then the wax goes where it is supposed to go: through the wick, not onto the paintwork. Soot.