This is the periodic table of the elements. Javier's teacher gives him four cards, each displaying information about an element, and asks him to put them in order of reactivity. The elements are carbon (C), helium (He), magnesium (Mg), and potassium (K). Javier arranges the elements in order from most reactive to least reactive, as shown in the diagram. Is Javier's arrangement correct? Why or why not?

How is electrolysis most commonly used to produce an energy source? a - splitting water molecules produces oxygen, which organisms breathe to fuel their bodies. b - splitting water molecules produces hydrogen gas, which is used to power machines through hydrogen fuel cells. c - splitting carbon dioxide molecules produces coal, a form of carbon that can be burned to produce heat. d - splitting carbon dioxide molecules produces natural gas, which can be burned to generate electricity in power plants.