Fehler:
Ca %2B HClO4 %3D Ca%28ClO4%292 %2B Cl2 %2B H2O
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Unerwartets Zeichen ('%')Ca %2B HClO4 %3D Ca%28ClO4%292 %2B Cl2 %2B H2O
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Unerwartets Zeichen ('%')