He used that name because if you lit hydrogen on fire it would catch. therefore, it was dangerous to be around. think of it as a kind of warning. :) hope that helps.
amount of product formed or amount of reactants used / time
an element's name, chemical symbol, atomic number, atomic mass.
IDK what you are even asking for
A hydrated substance will decrease in mass when heated since the water is being boiled away.
I hope this helps. Let me know if anything is unclear.
Gray matter hope this helps!
