Platinum crystallizes with a face-centered cubic unit cell.If the edge length of the unit cell is 393 pm,what is the radius of a platinum atom in picometers?

Question

Quizplus · Accepted Answer

In a face-centered cubic unit cell, there are 4 atoms at the corners and 1 atom at the center of each face. The radius of an atom can be calculated using the edge length of the unit cell (a) and the formula:

radius = (a√2)/2

Therefore, for platinum:
radius = (393 pm√2)/2
radius ≈ 139 pm

Platinum Crystallizes with a Face-Centered Cubic Unit Cell