Ko te pūhui matū ka hua ake i te tauhohenga o te hāora (O) me tētahi atu pūmotu, pērā i te rino (Fe), te konukura (Cu) me te hauota (N). I te nuinga o te wā, mā te ngingiha e puta ai te ōkai o te pūmotu e tahuna ana. Ko te waikura (Fe2O3) te ōkai o te rino.
The compound which is produced by the reaction of oxygen with another element, such as iron, copper or nitrogen. In many cases, the oxide is produced by the burning of the element. Rust (Fe2O3) is an oxide of iron.