Using the standard enthalpies of formation, what is the standard enthalpy of reaction?
co(g) + h2o(g) -> co2(g) + h2(g)

In this case, the reference forms of the constituent elements are O 2(g) and graphite for carbon. Using the values in the above table of standard enthalpies of formation, calculate the ΔHreactiono for the formation of NO2(g). The relevantstandard enthalpy of formation values from Table 1 are: O2(g): 0 kJ/mol.

CO(g) + H2O(g) -> CO2(g) + H2(g)=https://www.dropbox.com/s/8imewsdgt9t6m47/Screenshot%202016-10-18%2008.10.36.png?dl=0

The answer is the first option just took the test