C-10-Q032mediumsingle_mcq2PbS+3O2→?\mathrm{2PbS + 3O_2 \to ?}2PbS+3O2→?a2PbO+2SO2\mathrm{2PbO + 2SO_2}2PbO+2SO2bPbSO4\mathrm{PbSO_4}PbS