# What is the standard enthalpy of the reaction CO+H2O --> CO2+H2?

Nov 2, 2015

This is the water gas shift reaction; for which reams of thermodynamic data are available.

#### Explanation:

$C O \left(g\right) + {H}_{2} O \left(g\right) \rightarrow C {O}_{2} \left(g\right) + {H}_{2} \left(g\right)$

Jan 3, 2016

The standard enthalpy of reaction is +2.85 kJ.

#### Explanation:

We can use the standard enthalpies of formation of the reactants and products to calculate the standard enthalpy of reaction.

I list their values below the corresponding formulas.

Note that the substances must be in their most stable states at 298 K and 1 bar, so water is listed as a liquid.

color(white)(XXXXXXXXX)"CO"("g")color(white)(l) +color(white)(l) "H"_2"O"("l") →"CO"_2("g") +"H"_2("g")
ΔH_f^°("kJ/mol")color(white)(X) "-110.53"color(white)(XX) "-285.83"color(white)(XXl) "-393.51"color(white)(l)color(white)(XX)0

ΔH_"reaction"^° = sum(ΔH_f^°("products")) - sum(ΔH_f^°("reactants")) =" [1(-393.51) + 1(0) - 1(-110.53) - 1(-285.83)] kJ" ="2.85 kJ"