Two moles of phosphoric acid (H3PO4) contain, respectively: "x" moles of hydrogen atoms, "y" moles of phosphorous atoms, "z" moles of oxygen atoms.
Options:
a)9,3,12
b)2,2,2
c)3,1,4
d)6,2,8
in one mole of phosphoric acid you have 3 mol hydrogen, 2 mol phosphorus, and 4 mol oxygen. just multiply everything by 2 and you get 2 mol of phosphoric acid