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?
Best Answer
Lightning is not 'just light', it is according to this NOAA National Severe Storms Laboratory FAQ,
So, technically speaking, the mass of a lightning bolt could be the sum of all the electrons and the plasma within the electrical charge channel. (thank you to tpg2114)
Each electron has a mass of about $9.11 × 10^{-31}$ kilograms, but it would not really be feasible to exactly count how many electrons there are in a single lightning bolt, hence, not feasible to get an exact mass.