According to the Rifleman article, written by Dennis Marshall, the calcium has a great affinity for oxygen. When moisture is present it will absorb the oxygen from it, leaving the hydrogen to combine with either the Antimony or Arsenic. The An timony reacton produces the Stibine gas while the Arsenic one produces the Arsine gas. Tin plays no part in this, which incidently is Sn, Sb is Antimony. He gives the chemical reactions as ;
Sb2Ca3 + 3H2O(water) > 3CaO(lime) + 2SbH3 (Stibine)
As2Ca3 + 3H2O(water) > 3CaO(lime) + 2AsH3 (Arsine)
There is of course danger in bursting a battery apart, but this has nothing whatsoever to do with that. This has to do with a chemical reaction form allowing a lead/calcium alloy to be heated in mix with a lead/antimony/arsenic alloy. Bad News, according to the author. Not being a chemist, I plan on taking his word.
