Question

What is the electron configuration of each of the following ions? Use the noble gas abbreviation of the configuration. Enter the sublevels in the order in which they are filled. Do not enter empty sublevels. If the ion is isoelectronic to a noble gas, enter just the symbol for the noble gas, for example [Ne].

1. Sb^3-

2. Sn^2+

3 Cd^2+

4. Ca2+

5 F^1-

Answer 1

(1) Electronic configuration of Sb is [Kr] 4d¹⁰ 5s² 5p³

    Adding 3e^-'s to this we get Sb3-

So Sb^3- electronic configuration is [Kr] 4d¹⁰ 5s² 5p⁶

(2) Electronic configuration of Sn is [Kr] 4d¹⁰ 5s² 5p²

    removing 2e^-'s from this we get Sn²⁺

So Sn²⁺ electronic configuration is [Kr] 4d¹⁰ 5s⁰ 5p²

(3) Electronic configuration of Cd is [Kr] 4d¹⁰ 5s²

    removing 2e^-'s from this we get Cd²⁺

So Cd²⁺ electronic configuration is [Kr] 4d¹⁰ 5s²

(4) Electronic configuration of Ca is [Ar] 4s²

    removing 2e^-'s from this we get Ca²⁺

So Ca²⁺ electronic configuration is [Ar]

(5) Electronic configuration of F is [He] 2s² 2p⁵

   adding 1e^-'s to this we get F^-

So F^- electronic configuration is [He] 2s² 2p⁶