Answer:
Most atoms do not have eight electrons in their valence electron shell. Some atoms have only a few electrons in their outer shell, while some atoms lack only one or two electrons to have an octet. In cases where an atom has three or fewer valence electrons, the atom may lose those valence electrons quite easily until what remains is a lower shell that contains an octet. Atoms that lose electrons acquire a positive charge as a result because they are left with fewer negatively charged electrons to balance the positive charges of the protons in the nucleus. Positively charged ions are called cations. Most metals become cations when they make ionic
The Great Oxidation Event (GOE), sometimes also called the Great Oxygenation Event, Oxygen Catastrophe, Oxygen Crisis, Oxygen Holocaust,[2] or Oxygen Revolution, was a time period when the Earth's atmosphere and the shallow ocean first experienced a rise in oxygen, approximately 2.4 billion years ago (2.4 Ga) to 2.1–2.0 Ga during the Paleoproterozoic era.[3] Geological, isotopic, and chemical evidence suggests that biologically produced molecular oxygen (dioxygen, O2) started to accumulate in Earth's atmosphere and changed Earth's atmosphere from a weakly reducing atmosphere to an oxidizing atmosphere,[4] causing many existing species on Earth to die out.[5] The cyanobacteria producing the oxygen caused the event which enabled the subsequent development of multicellular forms.
Answer:
Oxygen
Explanation:
Water's formula is H20. Which is two hydrogen and one oxygen.
Answer:
c
Explanation:
chemicals can be found in every part of our lives
