🤓 Based on our data, we think this question is relevant for Professor Patterson's class at UCI.
Sodium chloride is face-centered cubic unit cell. Recall that a Face-Centered Cubic (FCC) unit cell has 4 atoms per unit cell.
And the formula for the edge length (a) of FCC unit cell:
Since the given is the distance between the center of potassium ion and chloride ion (not only the radius of one ion), the equation becomes:
In solid KCl the smallest distance between the centers of a potassium ion and a chloride ion is 314 pm. Calculate the length of the edge of the unit cell and the density of KCl, assuming it has the same structure as sodium chloride.