Actual Sizes of Molecules and Atoms

venerdì, Dicembre 18th, 2020

Actual Sizes of Molecules and Atoms,Exercises in nuclear reactor physics


Exercises in nuclear reactor physics by Ing. Giorgio Bertucelli


Exercise

Find the size of a water molecule if the molecular mass and density of water at melting point are approximately 18 and 1g/cm³

Solution
One gram-mole of water is 18 g_{m}. It occupies a volume of 18/1=18cm³. Since at the melting point the molecules are closely packed the volume of each molecule, assumed cubical, would be approximately


If each molecule were assumed spherical (more nearhly true) its volume would be roughly 2/3 of the above; so the radius of the molecule is

(altro…)