Question

Which of the following set of elements is written in order of their increasing metallic character?

• A. $\mathrm{Be},\mathrm{Mg},\mathrm{Ca}$
• B. $\mathrm{Na},\mathrm{Li},\mathrm{K}$
• C. $\mathrm{Mg},\mathrm{Al},\mathrm{Si}$
• D. $\mathrm{C},\mathrm{O},\mathrm{N}$

Answer 1

The correct option is A

$\mathrm{Be},\mathrm{Mg},\mathrm{Ca}$

Explanation for the correct options:

(A)$\mathrm{Be},\mathrm{Mg},\mathrm{Ca}$

• As we move down in a group in the periodic table, the atomic radius of the elements increases.
• It is become easy to lose an electron from the larger atomic size elements.
• Therefore the metallic character increases as we move down in a group.

Explanation for the incorrect options:

(B) $\mathrm{Na},\mathrm{Li},\mathrm{K}$

• The metallic character $\mathrm{Li}$ cannot be more than $\mathrm{Na}$, Because the atomic size of $\mathrm{Li}$ is less than $\mathrm{Na}$ so the loss of electron from $\mathrm{Li}$ is not easy as compared to $\mathrm{Na}$.

(C) $\mathrm{Mg},\mathrm{Al},\mathrm{Si}$

• As we move from left to right in the periodic table, then the metallic characteristics decrease.
• So in $\mathrm{Mg},\mathrm{Al},\mathrm{Si}$ metallic characteristics not increases.

(D) $\mathrm{C},\mathrm{O},\mathrm{N}$

• As we move from left to right in the periodic table, then the metallic characteristics decrease.

Hence, option (A) is correct., The order of increasing metallic character is $\mathrm{Be},\mathrm{Mg},\mathrm{Ca}$.