Fehler:
Cl2O7 %2B Ca%28OH%292 %3D Ca%28ClO4%292 %2B H2O
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Unerwartets Zeichen ('%')Cl2O7 %2B Ca%28OH%292 %3D Ca%28ClO4%292 %2B H2O
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Unerwartets Zeichen ('%')