O2- indicates an ion of oxygen having two extra electrons. I.e., since an oxygen atom normally has 8 protons and 8 electrons, this ion has 10 electrons (-10 charge) and 8 protons (+8 charge) giving it a charge of -2 (-10 + 8 = -2).
<span>Yes its H2O , the H2O and the OH- are acid/Base Conjugate pair................just like NH3 and NH4
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<span> The nuclear reactor powers plants to inhale heats that are needed to create/produce steam- (a gas that comes from liquid at its boiling point) The process is called fission. Fission entails the splitting on atoms in the nuclear reactor.
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It can be a compound or a single element. An element is a pure substance that cannot be separated into simpler substances by chemical or physical means. There are about 117 elements, but carbon, hydrogen, nitrogen and oxygen are only a few that make up the largest portion of Earth.
hopefully that helps