Is plastic considered a metal; if not, what category is ti in?
Anything that is more reactive will displace the less reactive element from one of its compounds. By forming water from oxide X, it shows that hydrogen is more reactive than X. Hydrogen can displace the metal from its oxide, so H > X Hydrogen does not displace the metal Y from its oxide, so Y is more reactive. Order of reactivity from high to low is Y > H > X
Metal y is the most reactive because hydrogen couldn't substitute its oxide and form water. But metal x oxide was substituted by hydrogen to form water. So the order of reactivity must be metal y, hydrogen and metal x in descending order of reactivity
