Question
Justify the position of hydrogen in the periodic table on the basis of its electronic configuration.
Solution
Hydrogen (Z=1) has electronic configuration 1s1. On one hand, its electronic configuration is similar to the outer electronic configuration (ns1) of alkali metals.
On the other hand, like halogens (having electronic configuration ns2np5 belonging to group 17 of the periodic table), it is short by one electron to the corresponding noble gas configuration (ns2np6).
Although hydrogen to a certain extent resembles both with alkali metals (Group I) and halogens (Group 17), yet it differs from them as well. Therefore, it is best placed separately in the periodic table.
On the other hand, like halogens (having electronic configuration ns2np5 belonging to group 17 of the periodic table), it is short by one electron to the corresponding noble gas configuration (ns2np6).
Although hydrogen to a certain extent resembles both with alkali metals (Group I) and halogens (Group 17), yet it differs from them as well. Therefore, it is best placed separately in the periodic table.
