Considering the elements `B, Al, Mg` and `K`, the correct order of their metallic character is

Options

A. `B lt A1 lt Mg lt K`
B. `B lt Mg lt A1 lt K`
C. `K lt Mg lt A1 lt B`
D. `Mg lt A1 lt B lt K`

Answer

A

Explanation

Electronegativity decreases and hence the metallic character increases within a group from top to bottom (i.e., A1 is more metallic than B ) .Further , electronegativity increases and hence the metallic character decreases from left to right along a period (i.e., metallic character decreases in the order : `K gt Mg gt A1)`. Thus the overall metallic character of the four elements increases in the order : `B lt A1 lt Mg lt K ,` i.e., option ( a) is correct.