Chapter 5 Lesson 2: Electron Arrangement in Atoms

Question 1

What are the three rules for writing the electron configurations of elements?

Answer 1

Three rules—the aufbau principle, the Pauli exclusion principle, and Hund’s rule

Question 2

the aufbau principle

Answer 2

Electrons occupy the orbitals of lowest energy first.

sublevels and principal energy level are always equal energy.

the S sublevel is always the lowest-energy sublevel.

However, the range of energy levels within a principal energy level can overlap the energy levels of another principal level.

Question 3

Pauli exclusion principle

Answer 3

An atomic orbital may describe at most two electrons, each with opposite spin direction

Question 4

Spin

Answer 4

a quantum mechanical property of electrons and maybe thought of as clockwise or counterclockwise.

Question 5

Hund’s rule

Answer 5

Electrons occupy orbitals of the same energy in a way that makes the number or electrons with the same spin direction as large as possible

Question 6

copper configuration

Answer 6

1s², 2s², 2p⁶, 3s², 3p⁶, 3d¹⁰, 4s¹