Answer
See explanation below.
Work Step by Step
The answer to this problem would be 800kJ/mol because the bond strength of CO2 is 799kJ/mol, not 745kJ/mol, as explained at the bottom of page 371. The calculation would then be: 8(799)+4(467)-4(413)-5(498)-2*X=2(1259) which gives 2X=1600 or X=800. Also, the value from the table is 839kJ/mol, not 1070kJ/mol, which is that of a triple bond between C and O.
