Pb(NO3)2+H2S=PbS+2HNO3
O2+2H2S=2S+2H2O
Br2+H2S=S+2HBr
HCl+H2S=не идёт
Pb(NO3)2 O2 Br2
Pb(NO3)2 + H2S => PbS↓ + 2 HNO3 2 H2S + 3 O2 => 2 SO2↑ + 2 H2O H2S + Br2 => 2 HBr + S↓
