Question

Given Element A,Atomic number 17 find pd group.

Answer 1

Answer:

Group # 7A , Period # 3

Explanation:

electronic configuration : 1s2 ,2s2,2p6,3s2,3p5

• the highest energy subshell determines the period number which here is 3.

• as for group number the number if electrons in the valence shell determines it. if the valence subshell is s then the number of electrons in it ie. 1 or 2 marks as the group number while for p subshell - number of electrons in the valence p subshell + the number of electrons in the adjacent s subshell = the group number. here 2 (of s) +5 (of p) = 7 is the group number