How is Fe (OH)2+O2+H2O-Fe (OH)3 balanced? Is it observation? How to balance Fe (OH)2+O 2+H 2O-Fe (OH)3? Is it observation?

How is Fe (OH)2+O2+H2O-Fe (OH)3 balanced? Is it observation? How to balance Fe (OH)2+O 2+H 2O-Fe (OH)3? Is it observation?

Balance according to conservation of redox electron transfer
Fe2 Fe3+ loses 1 electron
O2→OH - Get 4 electrons
So 1 O2 corresponds to 4 Fe2+
4Fe (OH)2+O2+2H2O==4Fe (OH)3

Fe (OH)2+O2+H2O=

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