Quantum Numbers and Electron Configuration

What does the principal quantum number (n) indicate about an electron in an atom?

How does the angular quantum number (l) affect the energy of subshells?

According to the Pauli exclusion principle, what can be concluded about electrons in the same orbital?

What is the total number of orbitals present in a p subshell?

What describes the magnetic quantum number (m_l)?

What is the correct order of filling orbitals according to the Aufbau principle?

Which of the following correctly describes the electron configuration for Neon (Ne)?

How many electrons can the 3d subshell hold?

In an electron configuration, paired electrons are represented by which of the following symbols?

Which of these elements has the following valence shell electron configuration: 4s² 4p²?

Which of the following statements about the periodic table and electron configurations is true?

Which of the following configurations illustrates the principle of minimizing paired electrons during electron filling?

Which of the following subshells can contain a maximum of 14 electrons?

Quantum Numbers

Electrons in an atom are described by four quantum numbers.
Principle quantum number (n): Positive integer, determines energy and orbital size.
Angular quantum number (l): Integer, determines shape of orbital. Values increase with increasing subshells (s<p<d<f).
Magnetic quantum number (ml): Integer, determines orientation of orbital in space. Orbitals in a subshell have 2l + 1 orientations.
Spin quantum number (ms): +1/2 or -1/2, describes electron spin orientation.

Pauli Exclusion Principle

No two electrons in an atom can have the same four quantum numbers.
Maximum of two electrons in each orbital.

Electron Configuration

The arrangement of electrons in atomic orbitals.
Aufbau principle: Electrons fill orbitals of lowest energy first.
Orbital diagram: Visual representation of electron distribution in orbitals using arrows (↑↓) for up and down spins.

Electron Configuration & Periodic Table

Main-group elements occupy s and p blocks.
Transition elements occupy d block.
Inner-transition elements occupy f block.

Abbreviated Electron Configuration

Shortened notation using the noble gas core. Brackets around previous noble gas followed by outer electron configuration.
Example: Na: [Ne] 3s¹

Valence Shell Electron Configuration

Electron configuration focusing only on outer shell electrons.
Example: Na: 3s¹

Unexpected Electron Configurations

Some elements have unexpected configurations (e.g., Cr, Cu).
Half-filled or completely filled d-orbitals, or half-filled or empty s-orbitals increase stability.
Example: Cr: [Ar] 3d⁵ 4s¹
Example: Cu: [Ar] 3d¹⁰ 4s¹

Explore the fundamental concepts of quantum numbers and electron configuration in atoms. This quiz covers the principles that dictate electron arrangement, the Pauli Exclusion Principle, and the significance of the periodic table in understanding electron distribution. Test your knowledge of how these concepts are interrelated.