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Lead is a chemical element on the periodic table with the atomic symbol Pb, atomic number 82, and standard atomic weight 207.2 u. Classified as a Post-Transition within Group 14 and Period 6 (p-block), lead possesses a ground-state electron configuration of [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p² distributed across 6 concentric Bohr electron shells (2 · 8 · 18 · 32 · 18 · 4) with 4 outer-shell electrons. Heaviest element with stable isotopes (Z = 82 is a nuclear proton 'magic number'; ²⁰⁸Pb is doubly magic with 82 protons and 126 neutrons). Stable endpoint of the ²³⁸U, ²³⁵U, and ²³²Th decay chains used by Clair Patterson to date Earth at 4.55 Ga.

⚛️ Interactive Periodic Table Lab: Explore Lead (Pb, Z = 82) in the CRV Science Dynamic Periodic Table & Bohr Orbital Lab to visualize its animated 2 · 8 · 18 · 32 · 18 · 4 electron shells, simulate live phase transitions from 0 K to 6,000 K, and compare periodic heatmaps across all 118 IUPAC elements.

Electron Shell Architecture and Ground-State Configuration

A neutral atom of lead contains 82 protons in its atomic nucleus balanced by 82 electrons occupying quantized atomic orbitals. In the Bohr-Sommerfeld and quantum-mechanical orbital models, these electrons populate 6 principal energy shells (K (n=1): 2e⁻, L (n=2): 8e⁻, M (n=3): 18e⁻, N (n=4): 32e⁻, O (n=5): 18e⁻, P (n=6): 4e⁻), terminating in the directional dumbbell-shaped p-orbital (azimuthal quantum number l = 1) with ground-state configuration [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p². Removing the most loosely bound valence electron from an isolated gaseous lead atom requires a first ionization energy of 716 kJ/mol, while its tendency to attract shared bonding electrons is quantified by a Pauling electronegativity of 2.33.

Periodic Table Position and Neighboring Elements

Within the periodic table, Lead occupies Period 6, Group 14 of the p-block (Post-Transition Metals). Along Period 6, it is flanked by Thallium (Tl, Z = 81) and Bismuth (Bi, Z = 83). Vertically within its periodic family, Lead shares valence orbital symmetry and homologous chemical trends with Tin (Sn), Flerovium (Fl). Learners can interactively compare Lead's orbital radii, ionization energy, and Pauling electronegativity against all neighboring elements in the Dynamic Periodic Table Lab.

Standard Phase, Melting Point, and Boiling Point Dynamics

At standard ambient temperature and pressure (298.15 K / 25 °C, 1 atm), elemental lead exists as a crystalline solid. As thermal energy increases, its crystal or molecular lattice undergoes solid-to-liquid fusion at a melting point of 600.61 K (+327.46 °C / +621.4 °F) and transitions to the vapor phase at a normal boiling point of 2,022 K (+1748.85 °C / +3179.9 °F), spanning a liquid thermodynamic range of 1421.39 K. In the CRV Science Dynamic Periodic Table, dragging the live temperature slider between absolute zero (0 K) and solar-photosphere temperatures (6,000 K) dynamically tracks Lead's state transitions in real time alongside enthalpy and entropy phase equilibria.

Quantitative Atomic and Thermodynamic Parameter Matrix

Characteristic Oxidation States and Coordination Chemistry

As a p-block post-transition metal situated to the right of the d-block, its valence electrons experience incomplete nuclear shielding from filled d (and in Period 6–7, f) subshells, resulting in higher electronegativity, softer metallic lattices, and the relativistic inert-pair effect. In chemical compounds, lead exhibits characteristic oxidation states of +2, +4. Depending on the electronegativity difference (Δχ) of its bonding partners—such as Oxygen (χ = 3.44), Fluorine (χ = 3.98), Chlorine (χ = 3.16), Nitrogen (χ = 3.04), Carbon (χ = 2.55), or Hydrogen (χ = 2.20)—lead forms redox-specific oxides, halides, hydrides, or coordination complexes governed by Gibbs free energy (ΔG = ΔH − TΔS).

Nucleosynthesis, Discovery History, and Elemental Origins

First identified or isolated in Ancient, Lead carries a distinct cosmological and geochemical signature. With atomic number Z = 82 beyond the iron-56 binding-energy peak, lead is synthesized astrophysically via neutron-capture nucleosynthesis—combining slow neutron capture (the s-process in asymptotic giant branch stars) and rapid neutron capture (the r-process in neutron-star mergers and core-collapse supernovae).

Biochemical Classification: Abiotic / Technological / Synthetic

In comparative biochemistry and systems physiology, Lead is classified as Abiotic / Technological / Synthetic. No known essential biological role; important in planetary geochemistry, astrophysics, materials science, or nuclear physics. Across terrestrial and marine ecosystems, its chemical speciation interacts with thermodynamics, enthalpy, entropy, chemistry.

Key Mechanistic Functions and Technological Uses

Heaviest element with stable isotopes (Z = 82 is a nuclear proton 'magic number'; ²⁰⁸Pb is doubly magic with 82 protons and 126 neutrons). Stable endpoint of the ²³⁸U, ²³⁵U, and ²³²Th decay chains used by Clair Patterson to date Earth at 4.55 Ga. Researchers and students can further investigate Lead's functional role alongside all 118 elements by launching the Interactive Periodic Table & Element Detective Lab on CRV Science Learn.

What is the electron configuration and valence shell structure of Lead (Pb)?

Lead (atomic number Z = 82) has the ground-state electron configuration [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p², distributing its 82 electrons across 6 shells as 2 · 8 · 18 · 32 · 18 · 4. Its outermost shell contains 4 electrons, placing Lead in Group 14, Period 6 (p-block) as a member of the Post-Transition Metals. You can watch these 82 electrons orbit the nucleus in real time in the Dynamic Periodic Table Bohr Lab.

What phase of matter is Lead at room temperature, and when does it melt or boil?

At standard room temperature (298 K / 25 °C) and 1 atm pressure, Lead is a crystalline solid. It melts at 600.61 K (+327.46 °C / +621.4 °F) and boils at 2,022 K (+1748.85 °C / +3179.9 °F). Using the 0–6,000 K temperature slider in the Interactive Periodic Table, you can observe Lead's exact solid, liquid, and gas transitions relative to all other elements.

How does Lead function in biochemistry, materials science, and technology?

Heaviest element with stable isotopes (Z = 82 is a nuclear proton 'magic number'; ²⁰⁸Pb is doubly magic with 82 protons and 126 neutrons). Stable endpoint of the ²³⁸U, ²³⁵U, and ²³²Th decay chains used by Clair Patterson to date Earth at 4.55 Ga. In biological systems, it is categorized under Abiotic / Technological / Synthetic, with principal oxidation states of +2, +4 and a first ionization energy of 716 kJ/mol.