Chyba:
Sn %2B NaOH %2B H2O %3D Na2%28Sn%28OH%295%29 %2B H2
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Neočakávaný ('%')Sn %2B NaOH %2B H2O %3D Na2%28Sn%28OH%295%29 %2B H2
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Neočakávaný ('%')