My chemistry teacher/book states that lightning is just light, and therefore has no mass and takes up no space (we're not very far through the book yet, it's defining matter).
However, I take issue with this statement - it feels wrong. My reasoning is this: Lightning, as far as I know, is simply electrical energy. Also, I believe that electrical energy needs a medium to travel through, right?
If this is true, wouldn't the air the lightning travels through be the mass and space the lightning takes up?