please tell if i am correct or wrong the electronic configuration of fe+ should be the same as that of chromium i.e. [Ar] 3d5 4s1 because both have the same number of electrons in the atom

CBSE Class 11-science Answered

please tell if i am correct or wrong the electronic configuration of fe+ should be the same as that of chromium i.e. [Ar] 3d5 4s1 because both have the same number of electrons in the atom

Asked by challenging_genius | 18 Jul, 2010, 12:00: AM

Expert Answer

Z = 26

Electronic configuration = 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁶ 4s²

So, when one electron is removed. it will be removed from 4s shell since it is the outermost shell.

Hence the electronic configuration of Fe⁺ becomes:

Electronic configuration = 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁶ 4s¹

The electronic configuration of Cr with atomic number of 25 is:

Electronic configuration = 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹

Thus, they are not same.

Always remember that whenever you have to write the electronic configuration of any ion, write the configuration of the atom and then if positively charged start removing electrons from the outermost shell and if negatively charged start adding electrons in the outermost shell.

never remove electrons from the atomic number as the configuration comes out to be wrong sometimes.

Answered by | 20 Jul, 2010, 12:23: PM