JEE Main 2023 · 25 January · evening · Single correct · +4 / −1
Which of the following represents the correct order of metallic character of the given elements?
- (a) K < Mg < Be < Si
- (b) Si < Be < Mg < K
- (c) Be < Si < Mg < K
- (d) Be < Si < K < Mg
Answer and solution
Answer (b) Si < Be < Mg < K
Solution
Chemistry ma’am · 3 steps
Place each element on the table first: metallic character rises to the left and down a group.
- The trend. Metallic character is how easily an atom gives up its valence electrons. It increases down a group and decreases across a period from left to right.
Element Group, period Nature Si Group 14, period 3 metalloid, far to the right Be Group 2, period 2 metal, but at the top of its group Mg Group 2, period 3 metal, below Be K Group 1, period 4 alkali metal, far left and low down - Compare in pairs. Si is a metalloid, so it is the least metallic. Be and Mg sit in the same group, and Mg lies below Be, so Mg is more metallic. K is in group 1 and a lower period, so it is the most metallic of all.
- So. The order is Si < Be < Mg < K, which is option (b).
The idea to keep. For metallic character, go left and go down. When elements sit in different groups and periods, first pick out any metalloid or non-metal: it is always below every true metal.
Answer from the NTA final answer key. Solution by PrepWiser.