Fehler:
Mg %2B HNO3 %3D Mg%28NO3%292 %2B N2O %2B H2O
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Unerwartets Zeichen ('%')Mg %2B HNO3 %3D Mg%28NO3%292 %2B N2O %2B H2O
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Unerwartets Zeichen ('%')