This abundance of carbon (soot) makes the smoke thick and black—akin to the smoke you might see from burning oil or rubber, which is rich in carbon-based particles.

Black smoke emerging from the chimney means the world's 1.4 billion Catholics don't yet have a new pope. White smoke means the cardinals have chosen a new leader of the church.

The 2025 Conclave begins today to elect Pope Francis’s successor. Here’s what time to watch for black or white smoke, how the process works, and where to stream it live.

The result is a deliberately inefficient combustion reaction, producing a high volume of unburnt carbon particles. This abundance of carbon (soot) makes the smoke thick and black—akin to the ...