Students use the terms isotope, atomic number, mass number, and atomic mass. Atomic Theory: Structure of the Atom: Students use the terms isotope, atomic number, mass number, and atomic mass to ...

Thank you for bringing to my attention the recent International Union of Pure & Applied Chemistry report “Atomic weights of the elements 2009” (C&EN, Dec. 20 ...

One hundred years ago the Harvard University chemist Theodore William Richards was awarded the 1914 Nobel Prize in Chemistry for his accurate determination of the atomic weights of many elements. This ...

For the first time those little numbers that appear beneath some of the commonest elements in the periodic table boxes are about to change from a single value to an interval of numbers An ...

I was surprised that C&EN would devote two columns to the letter by Harvey Carroll on the matter of atomic weight versus atomic mass (C&EN, Jan. 24, page 4). I realize the majority of the informed ...

Standard atomic weights, those numbers emblazoned under the elements on the periodic table, were once thought of as unchanging constants of nature. But researchers have tweaked the atomic weights of ...

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Two-dimensional (2D) atomic crystals and their heterostructures are an intense area of study owing to their unique properties that result from structural planar confinement. Intrinsically, the ...