Electronic configuration of an element is 1s^(2) 2s^(2) 2p^(6) 3s^(2) 3p^(5) than whatis atomic number of element which is situated bottom of this elements group ?

Electronic configuration of an element is 1s^(2) 2s^(2) 2p^(6) 3s^(2)

1.	Electronic configuration of an element is 1s^(2) 2s^(2) 2p^(6) 3s^(2) 3p^(5) than whatis atomic number of element which is situated bottom of this elements group ?
Answer» 49 25 35 18 Answer :C