Question

Which of the following reaction is possible

• A. ${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Cu}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{CuO}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$
• B. ${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Hg}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{HgO}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$
• C. ${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Al}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}{\mathbf{Al}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$
• D. None of these

Answer 1

The correct option is C

${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Al}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}{\mathbf{Al}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$

The explanation for the correct answer.

Option C

• In general, the more reactive a metal is: the more vigorously it reacts with other substances.
• The more easily it loses electrons to form positive ions (cations).
• Aluminium is more reactive than Iron.
• This implies Aluminium will displace Iron from Iron Oxide and form Aluminium Oxide (${\mathbf{Al}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}$).

${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Al}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}{\mathbf{Al}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$

• Hence, option C is the correct answer.

The explanation for the incorrect answer.

Option A

• As Iron is more reactive than Copper.
• This implies Copper will not displace Iron from Iron Oxide.
• Hence, the reaction is not feasible.

Option B

• As Iron is more reactive than Mercury.
• This implies Mercury will not displace Iron ($\mathbf{Fe}$) from Iron Oxide (${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}$).
• Hence, the reaction is not feasible.

Hence, The correct option is (C).