Question

What is the value for ∆Soreaction for the following reaction, given the standard entropy values? Fe2O3(s) + 3H2(g) 2 Fe(s) + 3H2O(g)

Answer 1

Answer: 141.55 J/K

Explanation: Value of ΔS can be obtained as:

`\Delta S=\sum{\text {Entropy of Products}-\sum{\text {Entropy of Reactants}}`

Standard entropy values are

`S^o(Fe_2O_3)=87.4J/molK`

`S^o(H_2)=130.59J/molK`

`S^o(Fe)=27.28J/molK`

`S^o(H_2O)=188.72J/molK`

`Fe_2O_3(s)+3H_2(g)\rightarrow 2Fe(s)+3H_2O(g)`

`\Delta S=\sum(2* 27.28J/molK+3* 188.72J/molK)-(3* 130.59J/molK+1* 87.4J/molK)=141.55J/K`