The mole fraction of Frenkel defects in a crystal at 1000 K is — Solid State Chemistry Question

💡 Solution & Explanation

The fraction of Frenkel defects is: n/N0 = sqrt(Ni/N0) * exp(-E / 2RT). Here, Ni/N0 \u2248 2. Given E = 73,600 cal/mol. -E / 2RT = -73600 / 4000 = -18.4. Since 18.4 = 8 * 2.3 = ln(10^8). Thus, n/N0 = sqrt(2) * exp(-ln(10^8)) = 1.41 * 10^-8.