Eight.
Oxygen has 6 electrons and shares two more with the hydrogen atoms in covalent bonds
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The covalent bonds that oxygen shares with hydrogen gives it a full outer shell of 8 electrons.
Carbon has four electrons in the outermost energy level, which is energy level two. It needs eight electrons to have this energy level filled.
There are 6 electrons in the outer most shell
Electrons in the outermost energy shell (valence shell) have the most energy.
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counting the shared electrons, 8.
The covalent bonds that oxygen shares with hydrogen gives it a full outer shell of 8 electrons.
The outermost ring of hydrogen, or the first energy level, can only hold a maximum of 2 electrons.