B. What is the electron configuration of an isolated Fe3+ cation?
(Use notation like [Ne]3s^23p^6 for your answer)
i put
[Ar]4s^23d^3
but i got it wrong
i don't know why
Ar is 18. Fe neutral atom is 26.
Ar 3d^6 4s2 = 18 + 8 = 26
Now remove the OUTSIDE 3 electrons.
We take away the 4s2 and 1 of the 3d to make [Ar] 3d^5 which is 18 + 5 = 23 and the Fe^+3 is 26-3=23.
To determine the electron configuration of an isolated Fe3+ cation, you need to first determine the electron configuration of neutral iron (Fe) by referencing the periodic table.
The atomic number of iron (Fe) is 26, which means it has 26 electrons when neutral. The electron configuration of neutral iron is:
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^6
Now, to find the electron configuration of Fe3+ cation, you need to consider that it has lost three electrons. This means you need to remove the 3 highest energy-level electrons from the neutral iron configuration.
The electrons to be removed from the highest energy level, in this case, are the 4s^2 electrons. So, remove these electrons:
1s^2 2s^2 2p^6 3s^2 3p^6 3d^6
This leaves you with the electron configuration of Fe3+ cation:
1s^2 2s^2 2p^6 3s^2 3p^6 3d^5
Thus, the correct electron configuration for an isolated Fe3+ cation is [Ar]3d^5.