Tausonite, a mineral composed of Sr, O, and Ti, has the cubic unit cell shown in the drawing.
(a) What is the empirical formula of this mineral?
(b) It is easy to see that Ti is coordinated by six oxygen atoms because the Ti atom is located at the center of the unit cell. To see the full coordination environment of the other ions, we have to consider neighboring unit cells. How many oxygens are coordinated to strontium?
