Electron Configuration Worksheet (Page 3 of 4) in pdf

Iodine Anion:

[Kr]5s

or 1s

3. Write the ground state electron configuration for neutral Hydrogen and then

write the electron configuration for an excited state of Hydrogen.

Hydrogen: 1s

Excited Hydrogen:2s

(this is one of many possible answers)

4. Write the ground state electron configuration for neutral Titanium and then

write the electron configuration for an excited state of Titanium.

Titanium: 1s

Excited Titanium: 1s

(this is one of many possible answers)

5. State in your own words the Pauli exclusion principle and Hund’s rule.

Pauli exclusion principle: If 2 electrons occupy the same orbital, they must

have opposite spins.

Hunds rule: If more than one orbital is available, add electrons with parallel

spins to the orbitals first before pairing up electrons.

The Aufbau principle works remarkably well for predicting the ground state

electron configurations for the majority of the elements on the periodic table.

However, there are some regions on the periodic table in which the Aufbau

principle is not entirely accurate in predicting the ground state configuration. In

general, in this class when asked to write the ground state configuration on an

assessment, we will choose an element that follows the Aufbau principle. Except,

we will expect you to be familiar with a few common exceptions. These

exceptions occur for elements near a ½ full or full d subshell. For some reason,

an electron will be promoted from the “lower energy” ns subshell to the (n-1)d

subshell when the d subshell can obtain a ½ full or full status. We see this

occurring with Chromium and Molybdenum (but not Tungsten), and in the case of

Copper, Silver and Gold.

6. Write the ground state electron configuration of the following neutral

elements in orbital notation, orbital notation with arrows and in short hand

noble gas notation.

Copper

Orbital notation: 1s

Orbital notation + Arrows:

Electron Configuration Worksheet Page 3