Question

The atomic weight of a trivalent metal is $x$. Calculate its electrochemical equivalent.

• A. $\frac{x}{96,500}$
• B. $\frac{x}{3\times 96,500}$
• C. $\frac{x}{3}$
• D. $\frac{3x}{96,500}$

Answer 1

The correct option is B

$\frac{x}{3\times 96,500}$

Explanantion for the correct option:

The atomic weight of the trivalent metal is $x$.

If the metal is in trivalent form, so it requires 3 electrons to be in atomic form. It is shown below:

$\underset{\mathrm{Trivalent}\mathrm{metal}}{{\mathrm{A}}^{3+}}+3{\mathrm{e}}^{-}\to \underset{\mathrm{Atomic}\mathrm{form}}{\mathrm{A}}$

To find the Electrochemical equivalent, we can use:

$\mathrm{Z}=\frac{\mathrm{M}}{\mathrm{F}\times \mathrm{z}}$

Where $\mathrm{Z}$ = Electrochemical equivalent,

$\mathrm{M}$ = Atomic mass of the metal,

$\mathrm{F}$ = 1 Faraday = 96500,

and $\mathrm{z}$ = Number of electrons in the equation.

Putting all the values, we get:

$\mathrm{Z}=\frac{\mathrm{x}}{96500\times 3}$

Therefore, the correct option is (B).