Given C(s) + O2(g) → CO2(g); ΔH = – 395 KJS(s) + O2(g) → SO2(g); ΔH = – 295 KJCS2(l) +3O2(g) → CO2(g) + 2SO2(g); ΔH = – 1110 KJThe heat of foramation of CS2(l) is

.eq.(1) +2 eq.(2) - eq (3)(eq. = equation)        C(s) + O2(g) → CO2(g); ΔH1 = – 395 KJ     2S(s) +2 O2(g) →2 SO2(g); ΔH2 =2( – 295) KJCO2(g) + 2SO2(g) →CS2(l) +3O2(g) ; ΔH3 = + 1110 KJ                                                                                         C(s) + 2S(s) → CS2(l) ;  ΔHf = ΔH1 + ΔH2 + ΔH3                                         ΔHf(CS2)  = +125 KJ/mole