thallium: Quick Facts

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Facts

Also Known As	Tl

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A periodic table entry for thallium highlights its atomic number 81, symbol Tl, atomic weight range, electron configuration, and name. Icons indicate thallium is a solid, hexagonal-structured, weakly basic metal at room temperature.

Line graph showing the first ionization energies of the elements as a function of atomic number, with peaks at noble gases like helium, neon, argon, krypton, xenon, and radon, and labeled elements at key points.

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Topics

chemical element boron group element hydrogen carbon sodium nitrogen sulfur phosphorus boron iodine fluorine zinc

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Key People

William Crookes

Sir William Crookes

British chemist

Periodic Table of the elements concept image (chemistry)

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Concept artwork on the periodic table of elements.

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