Given NH3(g)+3Cl2(g)→NCl3(g)+3HCl ; ΔH1
N2(g)+3H2(g)→2NH3(g); ΔH2
H2(g) + Cl2(g)→ 2HClg; ΔH3
The heat of formation of NCI3 in terms of ΔH1,ΔH2andΔH3 is
ΔH1+ΔH22−32ΔH3
NH3(g)+3Cl2(g)→NCl3(g)+3HCl;ΔH1
N2(g)+3H2(g)→2NH3(g);ΔH2
H2(g)+Cl2(g)→2HCl(g);ΔH3
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12N2(g)+32Cl2(g)→NCl3(g);ΔH4
ΔH4=ΔH1+ΔH22+32ΔH3