Metallic mercury is obtained by heating the mineral cinnabar (HgS)(HgS) in air: HgS(s)+O2(g)→Hg(l)+SO2(g)HgS(s)+O2( g)→Hg(l)+SO2(g) Part A Use the data in Appendix B in the textbook to calculate ΔH∘ΔH∘ (in kilojoules) for the reaction. Express your answer using four significant figures.