Errore:
H2S %2B Pb3%28CO3%292%28OH%292 %3D H2O %2B CO2 %2B PbS
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carattere inatteso ('%')H2S %2B Pb3%28CO3%292%28OH%292 %3D H2O %2B CO2 %2B PbS
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carattere inatteso ('%')