Can someone help me with electron configurations of ions?

Ok, so the instructions are: Write electron configurations for the following ions. Type your answer using the format [Ar].4s2.3d10.4p6. If the ion has a noble-gas configuration, enter only the noble-gas in brackets.

I've already entered these once, and webassign told me they were wrong. Can someone show me what I'm doing wrong?

The only one I got correct was Pb2+: [Xe].6s2.4f14.5d10

Cd2+: [Kr].4d10
Fe3+: [Ar].4s0.3d5
Zr4+: [Kr].4d2.5s2
Rh3+: [Kr].5s1.4d8
Ag+: [Kr].4d10.5s1

Thanks.

1. Cd2+: [Kr].4d10
2. Fe3+: [Ar].4s0.3d5
3. Zr4+: [Kr].4d2.5s2
4. Rh3+: [Kr].5s1.4d8
5. Ag+: [Kr].4d10.5s1

For #1, do you need to add the 3s0 before the 4d10, otherwise I have no problem with your answers for #1 or #2

For #3, It appears to be the configuration for the element

for #4 and #5 Try drawing the orbital notation and the removing the electrons with the same considerations you had for #1 and #2, and make certain the sublevels are in the correct order.

How about:

Ag+: [Kr].4d10
Rh3+: [Kr].5s1.4d5
Zr4+: [Kr]

I know that essentially, you take the normal electron configuration for the element, and add or subtract electrons based on whether your ion is positive or negative, right?

well you always subtract the highest energy level (n) electrons first

so ...

Sorry, it's been a long day. Teaching and parent/teacher conferences and I drive 1 hour to and from school.

Looks good, you may need to indicate 5s0 4d10 for silver.

1 hour to and from..i did that for about a year....no way , now i drive 13 mins