Chem help! PLEASE!?

Question

Choose the answer which lists the atoms Tl, As, S, Sn, and Hg in order of increasing effective nuclear charge experienced by the electrons in the n = 3 electron shell.




a) Sn, Tl, As, Hg, S
b) Tl, S, Hg, Sn, As
c) As, Hg, Sn, S, Tl
d) S, As, Sn, Hg, Tl
e) Sn, As, S, Hg, Tl


I have calculated the 3s oribital got 10 electrons...took the atomic number ( ex. TI, 22-10= 12) I did that for all of them..but Im getting the wrong order..the order I got was S, TI As Sn Hg...but obviously this isnt right..please help!

Answer 1

d) S, As, Sn, Hg, Tl

respectively the atomic numbers

16, 33, 50, 80 and 81.

I think you confused Ti (#22) with Tl (#81)