Atoms touch all the time! But to understand why we first have to decide what we mean by the word “touch.” Our normal conception of touching is grounded in the macroscopic world. I put a cup on the ...

When two hydrogen atoms get close enough, the electron from each atom feels an attraction from the proton in the other atom's nucleus. This attraction pulls the atoms together. The electrons end up ...

Have you ever seen a beautiful bunch of flowers packed tightly into a vase? A florist has to wiggle and arrange them perfectly so there are no empty holes. There are times when nature acts like a ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...