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

Hint: Here, some pairs of elements are given and we have to identify which pair of elements has no relation. Here, we will use the theory of the diagonal relationship of the periodic table elements.

Complete Step by Step Answer:
Let's understand the diagonal relationship of elements. The diagonal relationship says that some of the elements of certain groups of the period 2nd of the periodic table show resemblance in properties with the elements of the 3rd period of the next group, that is, there are diagonal relations that exist between the 2nd and 3rd period. This is termed the phenomenon of diagonal relationships.
2nd Period -- Li Be B C
3rd period -- Na Mg Al Si
 So, we see that Lithium (Li) shows similar properties that of Magnesium (Mg), Beryllium (Be) shows a resemblance with Aluminium (Al), and Boron (B) shows similarity with Silicon (Si).
Let's see the options. We find that all the above three pairs are given. And one pair, Li (Lithium)-Na (Sodium) is given. And this pair does not show the diagonal relation.
Therefore, option b is the answer.

Note: The periodic table defines a table where elements are arranged considering the increase of atomic numbers of them. The periodic table possesses 18 numbers of groups and seven numbers of periods. The properties namely, physical and chemical properties of elements in a certain group are the same. There are 118 numbers of elements present till now.