The Gibbs energy for the decomposition of Al_ | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) The relationship between Gibbs energy and cell potential is given by $\Delta G = -nFE_{cell}$.For the reaction $\frac{2}{3} Al_2O_3 \rightarrow \f

Vedclass · Accepted Answer

$2.5$

Vedclass · Answer

(C) The relationship between Gibbs energy and cell potential is given by $\Delta G = -nFE_{cell}$.For the reaction $\frac{2}{3} Al_2O_3 ightarrow \frac{4}{3} Al + O_2$,the number of electrons transferred $(n)$ is calculated as follows:$Al$ goes from $+3$ to $0$ (change of $3$ per $Al$ atom).For $\frac{4}{3}$ moles of $Al$,$n = \frac{4}{3} 	imes 3 = 4$.Given $\Delta G = +960 \ kJ \ mol^{-1} = 960000 \ J \ mol^{-1}$.Using $\Delta G = -nFE_{cell}$:$960000 = -4 	imes 96500 	imes E_{cell}$.$E_{cell} = -\frac{960000}{386000} \approx -2.487 \ V$.The magnitude of the potential difference required for the electrolytic reduction is approximately $2.5 \ V$.

The Gibbs energy for the decomposition of $Al_2O_3$ at $500^oC$ is as follows:
$\frac{2}{3} Al_2O_3 \rightarrow \frac{4}{3} Al + O_2$
$\Delta_rG = +960 \ kJ \ mol^{-1}$
The potential difference needed for the electrolytic reduction of aluminium oxide $(Al_2O_3)$ at $500^oC$ is at least ........ $V$.

Similar Questions

The correct statement/s about a Galvanic cell is/are:
$(a)$ Current flows from cathode to anode
$(b)$ Anode is the positive terminal
$(c)$ If $E_{cell} < 0$,then it is a spontaneous reaction
$(d)$ Cathode is the positive terminal

Colourless solutions of the following four salts are placed separately in four different test tubes and a strip of copper is dipped in each one of these. Which solution will turn Blue?

Explain the different conditions when an external potential is applied in the opposite direction in a galvanic cell (Voltaic cell) by taking a suitable cell example.

What is the density of a solution of sulphuric acid used as an electrolyte in lead accumulators (in $g \ mL^{-1}$)?

What is a secondary cell? Give examples of it.

Vedclass Test Series

Exam Paper Generator

Online Exam Module

The Gibbs energy for the decomposition of $Al_2O_3$ at $500^oC$ is as follows:$\frac{2}{3} Al_2O_3 \rightarrow \frac{4}{3} Al + O_2$$\Delta_rG = +960 \ kJ \ mol^{-1}$The potential difference needed for the electrolytic reduction of aluminium oxide $(Al_2O_3)$ at $500^oC$ is at least ........ $V$.