8. When X-rays are diffracted by a series of planes, the resultant intensity is sometimes zero; these are created by absent reflections; what is the number of absent reflections divided? a) 2 b) 10 c) 50 d) 100
Answer: a Explanation: These missing reflections are classified into two groups: those that are missing due to a quirk in the structure, and those that are missing due to the structure’s symmetry or kind of lattice. Systematic absences are what they’re called.