Question

What is the position of an element in the periodic table if its electron configuration is 1s2 2s2 2p6 3s2 3p5

Answer 1

The element in the periodic table with the provided electron configuration is Chlorine. Cl it is found as in element in Group 7 of the periodic table.

Answer 2

Answer : The position of an element in the periodic table is, Group 17 and Period 3

Explanation :

The given electronic configuration is, $1s^22s^22p^63s^23p^5$

Total number of electrons = 17

Number of valence electrons = 2 + 5 = 7

In the given configuration, 3 is the highest principle quantum number. Therefore, it belongs to the 3rd period in the periodic table.

If the elements belongs to the p-block then we have to determine the group number by,

Group number = Number of valence electrons + 10

Group number = 7 + 10 = 17

Hence, the position of an element in the periodic table is, Group 17 and Period 3