Iron undergoes a series of reactions in the presence of different reactants to form different compounds.

Fe ➡️ FeCl2 (Iron reacts with chlorine to form iron(II) chloride)FeCl2 ➡️ Fe(OH)2 (Iron(II) chloride reacts with sodium hydroxide to form iron(II) hydroxide)Fe(OH)2 ➡️ FeCO3 (Iron(II) hydroxide reacts with carbon dioxide to form iron(II) carbonate)FeCO3 ➡️ Fe3(PO)2 (Iron(II) carbonate reacts with phosphoric acid to form iron(II) phosphate)