Question

Water gas, mixturee of H2 and CO, is an important industrial fuel produced by the reaction of steam with red hot cake, essentially pur carbon: C + H2O ? CO + H2
(a) Assuming that coke has the same enthalpy of formation as graphite, calculate Ho298 for the reaction.

Answer 1

Answer:

$\boxed{\text{131.3 kJ/mol}}$

Explanation:

The formula for calculating the enthalpy change of a reaction by using the enthalpies of formation of reactants and products is

$\Delta_{\text{r}}H^{\circ} = \sum \Delta_{\text{f}} H^{\circ} (\text{products}) - \sum\Delta_{\text{f}}H^{\circ} (\text{reactants})$

                          C(s) + H₂O(g) ⇌ CO(g) + H₂(g)

ΔH°f/kJ·mol⁻¹:      0      -241.8      -110.5        0

$\begin{array}{rcl}\Delta_{\text{r}}H^{\circ} & = & -110.5 - (-241.8)\\& = & -110.5 + 241.8\\& = & \textbf{131.3 kJ/mol}\\\end{array}\\\text{The enthalpy of reaction is }\boxed{\textbf{131.3 kJ/mol}}$