Question

Which one of the following four metals would be displaced from the solution of its salts by the other three metals?

• A. $\mathrm{Mg}$
• B. $\mathrm{Ag}$
• C. $\mathrm{Zn}$
• D. $\mathrm{Cu}$

Answer 1

The correct option is B

$\mathrm{Ag}$

The explanation for correct option

(B) $\mathbf{Ag}$

Electrochemical series

• Various redox equilibria are arranged in order of their standard electrode potentials $\left(\mathrm{E}°\right)$ to form the electrochemical series.
• The electrochemical series is ordered with the greatest negative $\mathrm{E}°$ values at the top and the most positive at the bottom.
• The electrochemical series aids in the identification of substances that are good oxidizing and reducing agents.

Silver

• Since silver $\left(\mathrm{Ag}\right)$ is a non-reactive metal, it may be easily displaced.
• $\mathrm{Ag}$ would be displaced from its salt solution by metals such as magnesium $\left(\mathrm{Mg}\right)$, zinc $\left(\mathrm{Zn}\right)$, or copper $\left(\mathrm{Cu}\right)$.
• The half-standard reaction's reduction potential is the greatest among the metals.
• As a result, the silver $\left({\mathrm{Ag}}^{+}\right)$ ion is the most powerful oxidizing agent among the metals (ions).
• Other metals lose an electron, whereas the ${\mathrm{Ag}}^{+}$ ion gains.

The explanation for incorrect options

• Silver metal would be displaced from the solution of its salts by the other three metals
• Hence all other options (A), (C) and (D) are incorrect.

Therefore, the correct option is (B) $\mathbf{Ag}$.