I could be wrong (and if I am I am sure that someone with science credentials will correct me), but I do not think that it is a "chemical" reaction inasmuch as the emitted light is due to nuclear decay, i.e., radiation.
Sometimes you get what you pay for, sometimes you only pay more for what you get.
Three shots are not a "group"...they are a "few".
If the Bible is the literal, infallible, unerring word of God...where are all those witches I am supposed to kill? (Exodus 22:18)