Question

In the iron box, solution of metal X is placed. After some days holes appeared in the box. The metal (s), X may be:

• A. $\mathrm{Cu},\mathrm{Zn},\mathrm{Ag}$
• B. $\mathrm{Mg},\mathrm{Al},\mathrm{Zn},\mathrm{Ni}$
• C. $\mathrm{Sn},\mathrm{Pb},\mathrm{Ni}$
• D. $\mathrm{Ca},\mathrm{Na},\mathrm{Mg},\mathrm{Al}$

Answer 1

The correct option is D

$\mathrm{Ca},\mathrm{Na},\mathrm{Mg},\mathrm{Al}$

Metals are arranged in descending order of their reactivities in the reactivity series, which is also known as the activity series.

Explanation for correct answer

(D) $\mathrm{Ca},\mathrm{Na},\mathrm{Mg},\mathrm{Al}$ , This can be explained on the basis of reactivity series.

Only those metals are able to create holes which are reactive than $\mathrm{Fe}$(Iron). This series can be written as:

$\mathrm{K}>\mathrm{Na}>\mathrm{Li}>\mathrm{Ba}>\mathrm{Sr}>\mathrm{Ca}>\mathrm{Mg}>\mathrm{Al}>\mathrm{Mn}>\mathrm{Zn}>\mathrm{Cr}>\mathrm{Fe}>\mathrm{Co}>\mathrm{Ni}>\mathrm{Sn}>\mathrm{Pb}>\mathrm{H}>\mathrm{Cu}>\mathrm{Hg}>\mathrm{Ag}>\mathrm{Au}$

Hence from the series it can be clearly seen that $\mathrm{Ca},\mathrm{Na},\mathrm{Mg},\mathrm{Al}$ are more reactive which can create holes.

Hence the correct option is D.