Oxide copper, so it displaces copper (II) oxide to form zinc oxide: Apart from metals, hydrogen can also displace metal oxides to form hydrogen oxide, also known as water: Since metals that are reactive form oxides that are stable, some metal oxides must be electrolyzed to be reduced. This includes sodium oxide, potassium oxide, calcium oxide, magnesium oxide, and aluminium oxide. The oxides must be molten before immersing graphite electrodes in them: Oxides typically react with acids or bases, sometimes both. Those reacting only with acids are labeled basic oxides. Those reacting only by bases are called "acidic oxides". Oxides that
Cerium(III) oxide Cerium(III) oxide Cerium(III) oxide, also known as cerium oxide, cerium trioxide, cerium sesquioxide, cerous oxide or dicerium trioxide, is an oxide of the rare-earth metal cerium. It has chemical formula CeO and is gold-yellow in color. Cerium oxide is used as a catalytic converter for the minimisation of CO emissions in the exhaust gases from motor vehicles. When there is a shortage of oxygen, cerium(IV) oxide is reduced by carbon monoxide to cerium(III) oxide: When there is an oxygen surplus, the process is reversed and cerium(III) oxide is oxidized to cerium(IV) oxide: Major automotive applications for cerium(III) oxide are, as