452

You visited us 452 times! Enjoying our articles? Unlock Full Access!

Electrochemical Cells, Galvanic Cells

The Gibbs ene...

Question

The Gibbs energy for the decomposition of $A l_{2} O_{3} a t 500^{\circ} C$ is as follows : $\frac{3}{2} A l_{2} O_{3} \to \frac{4}{3} A l + O_{2}; Δ_{r} G = + 960 k J m o l^{- 1}$

The potential difference needed for the electrolytic reduction of aluminium oxide $(A l_{2} O_{3}) a t 500^{\circ} C$ is at least :

2.5 V

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

3.0 V

No worries! We‘ve got your back. Try BYJU‘S free classes today!

4.5 V

No worries! We‘ve got your back. Try BYJU‘S free classes today!

5.0 V

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A $2.5 V$
$\frac{3}{2} A l_{2} O_{3} \to \frac{4}{3} A l + O_{2}$
$n = \frac{2}{3} \times 2 \times (+ 3)$
$= 4$
Total charge $= 4$

$Δ_{r} G = + 960 k J m o l^{- 1}$
Now, $Δ G = - n F E$
$960 \times 1000 = - 4 \times 96500 \times E$
$E = - 2.5 V :$ So potential difference needed $= 2.5 V$

Suggest Corrections

Similar questions

A l_{2} O_{3}

500

^{o} C

2 / 3 A l_{2} O_{3} \to 4 / 3 A l + O_{2}; Δ_{r} G = + 966

A l_{2} O_{3}

500^{o}

A l_{2} O_{3}

500^{o} C

\frac{2}{3} A l_{2} O_{3} \to \frac{4}{3} A l + O_{2}; Δ G = + 966 k J m o l^{- 1}

(A l_{2} O_{3})

500^{o} C

A l_{2} O_{3}

500^{\circ} C

\frac{2}{3} A l_{2} O_{3} \to \frac{4}{3} A l + O_{2}; △_{r} G = + 966 k J m o l^{- 1}

A l_{2} O_{3}

500^{\circ}

A l_{2} O_{3}

500^{0} C

\frac{2}{3} A l_{2} O_{3} \to \frac{4}{3} A l + O_{2}

Δ_{r x n} G = + 960 k J m o l^{- 1}

(A l_{2} O_{3})

500^{o} C

A l_{2} O_{3}

500^{0} C

\frac{2}{3} A l_{2} O_{3} ⟶ \frac{4}{3} A l + O_{2}

△_{r} G = + 960 k J m o l^{- 1}

(A l_{2} O_{3})

500^{0} C

Join BYJU'S Learning Program