Question

An engineer is trying to dissolve CaO in AgCl crystal lattice to form a substitutional solid solution.  Her/his efforts are likely to produce:

A. a substitutional solid solution with complete solubility

B. an interstitial solid solution

C. a substitutional solid solution with near complete solubility and a small grain size

D. an interstitial solid solution with near complete solubility and with a small grain size

E. a mixture of CaO and AgCl with almost no solid solubility

Answer 1

Solution:

The correct option will be C.

Since, both CaO and AgCl are cubic crystals, therefore they form substitutional solid solution.

Again, the size difference between Ca2+ and Ag+ is very small, thus they form substitutional solid solution.

The valency of Ca is +2 and that of Ag is +1. Hence, they can not form completely soluble solid solution.