Lasted edited by Andrew Munsey, updated on June 15, 2016 at 1:39 am.
Oxygen is a There was an error working with the wiki: Code[2] or There was an error working with the wiki: Code[3] bonded to other elements.
Unbound oxygen (also called molecular oxygen, or dioxygen, O2, a There was an error working with the wiki: Code[4]) first appeared in significant quantities on Earth during the There was an error working with the wiki: Code[5] era (between 2.5 billion years ago and 1.6 billion years ago) as a product of the There was an error working with the wiki: Code[6] action of early There was an error working with the wiki: Code[7]s (There was an error working with the wiki: Code[8] and There was an error working with the wiki: Code[9]). The presence of large amounts of free oxygen may have driven most of the organisms then living to extinction.There was an error working with the wiki: Code[1] The atmospheric abundance of free oxygen in later geological epochs and up to the present has been largely driven by There was an error working with the wiki: Code[10] organisms roughly three quarters of the free element being produced by There was an error working with the wiki: Code[11] in the oceans, and one quarter from terrestrial There was an error working with the wiki: Code[12]s.
• Latest
• News