Trắc nghiệm: (I) 2HI(k)⇌H2(k)+I2(k)(II) CaCO3(r)⇌CaO(r)+CO2(k)(III) FeO(r)+CO(k)⇌Fe(r)+CO2(k)(IV) 2SO2(k)+O2(k)⇌2SO3(k),(I) 2HI(k)⇌H2(k)+I2(k);(II)CaCO3(r)⇌CaO(r)+CO2(k);(III)FeO(r)+CO(k)⇌Fe(r)+CO2(k)(IV)2SO2(k)+O2(k)⇌2SO3(k)