Atomic Properties of Pb
- Atomic Number of Pb
- 82
- Atomic Mass of Pb
- 207.2000 u
- Electron Configuration
- [Xe] 4f14 5d10 6s2 6p2
- Electronegativity
- 1.87
- Block
- p-block
- Group
- 14
- Period
- 6
Lead is dense because each atom carries a heavy nucleus and packs into a metallic solid. That density, combined with high atomic number, makes lead effective at attenuating X-rays and gamma rays. Carefully designed barriers protect workers and patients around imaging and radiation sources. Thickness, radiation energy, geometry, and secondary exposure all matter; a random sheet is not a complete shielding plan.
The same element anchors lead-acid batteries. Lead and lead dioxide electrodes react with sulfuric acid during discharge, converting chemical energy to electrical energy, then reverse during charging. These batteries remain important for vehicle starting and energy storage. Mature collection systems recover much of their lead, but manufacturing, recycling, and informal handling can expose workers and communities if containment fails.
Lead is a cumulative toxicant with no known safe exposure level for children. It can damage brain development, blood formation, kidneys, and other systems. Historical lead paint, pipes, gasoline additives, solder, pottery glazes, contaminated soil, and industrial emissions created persistent exposure routes. Metallic lead quietly behind a barrier and lead dust in a home are entirely different risk scenarios.
Its symbol Pb comes from plumbum, the Latin source of “plumbing.” Roman use of lead pipes is memorable, but modern problems come from many products and infrastructures built much later. Four stable isotopes occur naturally; three are final products of uranium or thorium decay. Their ratios support geological dating.
Lead is a Tinkerer that forces lifecycle thinking. Density protects against radiation, reversible chemistry starts engines, and toxicity makes enclosure, monitoring, collection, and responsible recycling inseparable from every legitimate use.