The correct option is D 145
Given reactions are,
eq.(1)
C(s)+O2(g)→CO2,(g); △H1=−94.3 kcal/mol
eq.(2)
CO(g)+12O2(g)→CO2(g); △H2=−67.4 kcal/mol
eq.(3)
O2(g)→2O(g); △H3=117.4 kcal/mol
eq.(4)
CO(g)→C(g)+O(g); △H4=230.6 kcal/mol
The required reaction,
C(s)→C(g) can be obtained by the combination,
Target equation = eq.(1)−eq.(2)−12eq.(3)+eq.(4)
So, enthalpy change will be:
△H=△H1−△H2−12△H3+△H4
putting all the values,
=−94.3+67.4−58.7+230.6=145 kcal/mol.