Electron Configuration Review Method Electron Configuration NOTES

Only the highest number FIRST, COLOR-CODE YOUR PERIODIC TABLE TO of electrons present in 2 2 6 2 6 2 10 each orbital (sub-level) SHOW THE ORBITALS. Long 1s , 2s , 2p , 3s , 3p , 4s , 3d is written in the electron 1. The s orbital is shaped and can hold electrons. configuration.

2. The p orbital is shaped and can hold electrons. Use the element symbol of the noble gas in the 3. The d orbital is shaped and can hold electrons. previous energy level enclosed in square Short 2 10 4. The f orbital is shaped and can hold electrons. [Ar] 4s , 3d bracket then append the remaining orbital notation. (The “last noble Electron Configuration – Longhand Method gas you pass”)

Identify the following elements: Hint: if you add up all the exponents, it will equal the number of electrons. Also, if you look at the last number/letter combination, you can go directly to that spot on the periodic table to determine the element.

2 2 6 2 6 2 3 Example: 1s 2s 2p 3s 3p 4s 3d (This has a total of 23 electrons which

equals the atomic number of V – Vanadium.) Also, if you go to the third level

of the d-block and count over 3 electrons you will see V. Both ways are good.

1. 1s2 2s2 2p6 3s2 3p5

2. 1s2 2s2 2p4

3. 1s2 2s2 2p6 3s2 3p6 4s2 3d7 Example: Electron configuration notations for Zinc, Zn [Z=30] 4. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 1s2 2s2 2p6 3s2 3p6 4s2 3d10 5. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d9 Or [Ar] 4s2 3d10 2 2 6 2 6 2 10 4 6. 1s 2s 2p 3s 3p 4s 3d 4p When writing electron configurations, the total number of electrons 7. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1 must equal the (longhand notation only) 8. The electrons will fill the orbitals from left to right on the periodic table 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d9 (in the same order as the atomic numbers) because it is arranged in order of to highest energy levels.

7. states that every Write the electron configuration for the following elements using the electron has a unique set of quantum numbers (electron configuration). longhand method. Then write it shorthand (Noble Gas) notation. The quantum numbers are EXCLUSIVELY unique to each electron.

Gold [Z=78] 8. Identify the following Elements: [ ]

Silver [Z=47]

Uranium [Z=92]

9. Draw the orbital diagram for: (follow the diagram on #8 above) Hint: it may help to write the electron configuration first.

Nitrogen [Z=7] Which elements are represented by these noble gas configurations? [Ar] 4s2 3d6 .

2 [Xe] 6s . Oxygen (Z=8) [Ne] 2 1 3s 3p . [Kr] 5s2 4d10 5p2 .

Another way to represent the electrons is called . Argon [Z=18]

This is similar to the electron configuration, but it includes a diagram of the electrons represented by up and down . The arrows indicate the of the electrons within the orbitals.

Potassium [Z=19] 5. The states that electrons will fill lower energy levels before filling higher energy levels. (Filling bottom/lower energy levels “off the bottom” sounds similar to Aufbau may help remember this name.) See textbook page 105 (and colored handout) 2 2 5 a. 1s 2s 2p

6. states that orbitals of equal energy are occupied by one electron (all three “p” orbitals will be filled with one electron first, then other electrons will share the “p” orbitals). Also, the spins will be parallel until the orbitals are shared. b. 1s2 2s2 2p6 3s2 3p6 4s2 3d 4 See textbook example page 106.