C-10-Q032mediumsingle_mcq2PbS+3O2→?\mathrm{2PbS + 3O_2 \to ?}2PbS+3O2→?a2PbO+2SO2\mathrm{2PbO + 2SO_2}2PbO+2SO2bPbSO4\mathrm{PbSO_4}PbSO4cPb+SO3\mathrm{Pb + SO_3}Pb+SO3dPbS2\mathrm{PbS_2}PbS2