I was watching an explanation (found here: youtu.be/yTkojROg-t8 ) on nuclear fission. In the video, he described the process of fission to happen one a random neutron smashes into a uranium nucleus. This causes the necleus to split into krpyton and barium, taking part of the nucleon and electrons with it, along with a few extra neutrons. The extra neutrons then smash into other uranium nucleuses, causing the chain reaction. My question is, if you start with only x electrons in the original uranium atom, you must run out of electrons soon in the chain reaction. Where do the extra electrons needed to continue the chain reaction come from?