Question

The set of elements that differ in a mutual relationship from those of the other sets is:

• A. $Be–Al$
• B. $Li–Na$
• C. $B–Si$
• D. $Li–Mg$

Answer 1

The correct option is B $Li–Na$

A diagonal relationship is said to exist between certain pairs of diagonally adjacent elements in the second and third periods (first 20 elements) of the periodic table.
Out of the given options, pair (b) $Li-Na$ do not show diagonal relationship as both belongs to same group and are not placed diagonally.