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 ...

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 ...

This video is an interactive lesson in calculating an atom’s mass and atomic number. Atoms consist of a nucleus containing protons and neutrons, surrounded by electrons in shells. The numbers of ...

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 ...

Body mass index (BMI) estimates how healthy your weight is based on your height. There's no "perfect weight" that fits everyone, but BMI can help most adults understand their weight-related health ...

Adjusted body weight is used to calculate weight, which considers lean and fat mass. This tool can help provide more precise medical and nutritional assessments. Healthcare professionals often use ...

How do we know the mass of a planet originally appeared on Quora - the knowledge sharing network where compelling questions are answered by people with unique insights. Answer by Geoffrey Widdison on ...

Body mass index (BMI) can help you see if your weight is raising your risk for health problems. It uses a formula to compare how much you weigh with how tall you are. A BMI lower than 18.5 is ...