Question

For interstitial solid solutions, atomic radii difference must not differ by more than ________

(a) 25%

(b) 37%

(c) 59%

(d) 73%

I have been asked this question by my college professor while I was bunking the class.

This intriguing question comes from Hume Rothery’s Rules, Types of Solid Solutions in portion Solid Solutions & Crystallography of Engineering Material & Metallurgy

Answer 1

The correct answer is (c) 59%

Best explanation: For interstitial solid solutions, Hume Rothery’s rules state that the radius of solute atoms must not be larger than solvent atoms by more than 59%. Moreover, they should have similar electronegativities and valencies.