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

2 Answers
Nov 2, 2015


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


#CO(g) + H_2O(g) rarr CO_2(g) + H_2(g)#

For leading references see here.

Jan 3, 2016


The standard enthalpy of reaction is +2.85 kJ.


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"#