When you burn steel wool, it actually gets heavier because it reacts with oxygen in the air. Steel wool is made of iron, and during burning, the iron combines with oxygen to form a new substance called iron oxide (which is a kind of rust). Even though it looks like the steel wool is burning away, it’s really gaining weight because oxygen atoms from the air are attaching to the iron. So instead of losing mass, it adds more—making it heavier after the burn. Follow our community of deep thinkers, q