Quantum Numbers and Electron Configuration

These flashcards cover key vocabulary and concepts related to quantum numbers, electron configurations, periodic trends, naming compounds, and redox reactions.

Quantum number n

Represents the energy level or shell.

Quantum number l

Represents the orbital shape; values are 0=s, 1=p, 2=d, 3=f.

Quantum number mₗ

Represents orbital orientation with values from −l to +l.

Quantum number mₛ

Represents electron spin; can be +½ or −½.

Heisenberg Uncertainty Principle

States you cannot know both position and momentum of an electron exactly at the same time.

Hund’s rule

Electrons will fill empty orbitals before pairing up.

Pauli exclusion principle

No two electrons can have the same four quantum numbers.

Ground state

The lowest-energy arrangement of electrons in an atom.

Excited state

A higher-energy state that results from absorbing energy.

Quantized

Indicates that only certain energy levels are permitted.

Wavelength

The distance between successive peaks of a wave. That is often found in electromagnetic radiation, light.

Frequency

The number of waves that pass a point in one second.

Degenerate orbitals

Orbitals that have the same energy.

Orbitals

Regions in space where electrons are likely to be found.

Photon

A discrete packet of light energy.

Isoelectronic

Having the same number of electrons.

Valence electrons

Electrons located in the outermost shell.

Core electrons

in the innermost shell

Fe electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁶.

Fe²⁺ (iron(II)) electron configuration

[Ar] 3d⁶.

Na⁺ electron configuration

1s² 2s² 2p⁶.

P³⁻ electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶.

Barium noble-gas configuration

[Xe] 6s².

Calcium valence electron configuration

4s².

Chlorine valence electron configuration

3s² 3p⁵.

Lead (Pb) electron configuration

[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p².

Isoelectronic species

F⁻ and Na⁺ both have 10 electrons; I⁻ and Xe both have 54 electrons.

Paramagnetic

Characteristic of atoms or ions with unpaired electrons.

Diamagnetic

Characteristic of atoms or ions where all electrons are paired.

Naming of PbCO₃

Lead(II) carbonate (ionic compound).

Naming of HgBr₂

Mercury(II) bromide (ionic compound).

Naming of Co(HCO₃)₂

Cobalt(II) hydrogen carbonate.

Naming of NO

Nitric oxide.

Naming of SiF₄

Silicon tetrafluoride.

Naming of Ca(CH₃COO)₂

Calcium acetate.

Naming of K₂SO₄

Potassium sulfate.

Atomic line spectra

Produced by electrons dropping from higher to lower energy levels.

Colored lines in spectra

Result from photons emitted as electrons move to lower energy levels.

Periodic trends in atomic radius

Rubidium (Rb) has the largest atomic radius. Atomic radius generally increases down a group and decreases across a period due to increased nuclear charge and electron shielding.

Highest first ionization energy

Boron (B) has the highest IE₁ compared to beryllium.

Smallest radius comparison

Mg²⁺ has the smallest radius compared to Ca²⁺ and Ca.

Smallest radius between ions

Fluorine (F) is smaller than fluoride ion (F⁻).

Highest effective nuclear charge

Chlorine (Cl) has the highest Zeff among the options.

Most favorable electron affinity

Fluorine (F) has the most favorable electron affinity.

First ionization energy of Na

The reaction is Na(g) → Na⁺(g) + e⁻.

First electron affinity of Cl

The reaction is Cl(g) + e⁻ → Cl⁻(g).

Second ionization energy of Ca

The reaction is Ca⁺(g) → Ca²⁺(g) + e⁻.

Second electron affinity of S

The reaction is S⁻(g) + e⁻ → S²⁻(g).

Oxidation number of S in SO₄²⁻

+6.

Oxidation number of N in NH₄⁺

–3.

Oxidation number of Ca in CaH₂

+2.

Oxidation number of Fe in FeCl₃

+3.

Oxidation number of O in O²⁻

–2.

Reduction in 3 Fe²⁺ + 2 Al → 3 Fe + 2 Al³⁺

Fe²⁺ is reduced.

Oxidation in 3 Fe²⁺ + 2 Al → 3 Fe + 2 Al³⁺

Al is oxidized.

Reducing agent in the reaction

Al is the reducing agent.

Oxidizing agent in the reaction

Fe²⁺ is the oxidizing agent.