Determine the number of atoms per unit cell for each metal.

(b) Tungsten

Video transcript

Hey everyone today, we're being asked to identify the number of atoms in the unit cell of chromium as depicted below. So let's go ahead and take a look at this. So any unit cell, we know that atoms have different contributions depending on their locations. So for corner atoms which are right in red corner atoms, They will have a contribution of 1/8 of an atom. And let's write this as the contribution contribution. For Adams in the center, their first center, They contribute one adam. And for Adams in a face of a cube. And for Adams in the face of a cube They will have a 1/2 Adam contribution and for edges they will have a 1/ contribution 1/4. So this in mind if we take a look in the chromium atom that we have here or the chromium unit cell, I should say we have eight corner atoms which I'll just quickly scribble in with the red, we have eight corner atoms And exactly one central atom right here. It's not in any of the faces, it is smack in the center so the eight corner atoms each have a contribution of 1/ which means in total they account for about one atom and the center adam has just a contribution of one. So just be one times one, which gives us again one adam. So totally. This brings us to a final answer of two atoms per unit cell. Unit cell and that is our answer. I hope this helps. And I look forward to seeing you in the next one