question_answer

From the Ellingham graphs on carbon, which of the following statements is false?

A) \[C{{O}_{2}}\] is more stable than \[CO\] at less than 983 K

B) \[CO\] reduces \[F{{e}_{2}}{{O}_{3}}\] to Fe at less than 983 K

C) \[CO\]  is less stable than \[C{{O}_{2}}\] at more than 983 K

D) \[CO\] reduces \[F{{e}_{2}}{{O}_{3}}\] to Fe in the reduction zone of Blast furnace

Correct Answer: C

Solution :

:    Ellingham diagram for the reducing  nature of carbon Ellingham diagram for the reduction of haematite                  Below \[983K,\text{ }\Delta {{G}^{o}}\] for the formation of \[C{{O}_{2}}\] is more negative than \[\Delta {{G}^{o}}\] for the formation of \[CO\], so \[C{{O}_{2}}\] is more stable. At temperature above \[983K\] \[\Delta {{G}^{o}}_{formation}\] of \[CO\] is more negative than \[\Delta {{G}^{o}}_{formation}\] of \[C{{O}_{2}}\], so \[CO\] is more stable. So statement is false.                                   \[\Delta {{G}^{o}}_{formation}\] of \[C{{O}_{2}}\] from \[CO\]  is more negative than \[\Delta {{G}^{o}}_{formation}\] of \[F{{e}_{2}}{{O}_{3}}\]. This means that \[F{{e}_{2}}{{O}_{3}}\] can be reduced by \[CO\] below\[1073K\].