Fehler:
Au %2B KCN %2B O2 %2B H2O %3D KOH %2B KAu%28CN%292
^
Unerwartets Zeichen ('%')Au %2B KCN %2B O2 %2B H2O %3D KOH %2B KAu%28CN%292
^
Unerwartets Zeichen ('%')