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The thermite reaction shown below releases a tremendous amount of energy:

8Al + 3Fe3O4 → 9Fe + 4Al2O3
Which of the following statements is not true?
A. Aluminium is oxidized
B. Iron is reduced
C. Oxidation number of Al goes from 0 to +3
D. Aluminium is the reducing agent
E. Three electrons are transferred from each Al atom to each Fe atom

1 Answer

3 votes

Final answer:

In the thermite reaction, aluminium is oxidized and acts as the reducing agent, while iron oxide is reduced to form iron. Statement E is incorrect, as three electrons are not transferred from each Al atom to each Fe atom; instead, the transfer involves a total of 9 electrons from 3 Al atoms to 2 Fe3+ ions.

Step-by-step explanation:

The thermite reaction involves aluminium being oxidized and iron being reduced. The correct balanced chemical equation for the thermite reaction is:

2 Al(s) + Fe₂O₃(s) → 2 Fe(s) + Al₂O₃(s) +heat

This reaction is highly exothermic, producing enough heat to melt the iron. Based on the student's provided equation (which follows a multiple of the correct stoichiometry), we can analyze each statement:

  • A. Aluminium is oxidized: true, as Al goes from 0 to +3 in oxidation state.
  • B. Iron is reduced: true, as Fe3O4 is reduced to Fe.
  • C. Oxidation number of Al goes from 0 to +3: true, evident from the aluminum gaining an oxidation state of +3.
  • D. Aluminium is the reducing agent: true, since it loses electrons and reduces Fe3O4.
  • E. Three electrons are transferred from each Al atom to each Fe atom: this statement is not true. In reality, 3 Al atoms donate a total of 9 electrons to 2 Fe3+ ions to reduce them to Fe. Thus, it's not a one-to-one transfer of electrons from each Al to each Fe.

The incorrect statement is E: Three electrons are transferred from each Al atom to each Fe atom.

User Rodrigo Rubio
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