For example, Krypton Factor (7)
I believe the answer is:
element
I believe this clue is a double definition.
'for example krypton' is the first definition.
(I know that Kr is a type of element)
'factor' is the second definition.
(I know that factor can be written as element)
(Other definitions for element that I've seen before include "Component of periodic table" , "eg Fire, air" , "Chemical building-block" , "Comfort zone" , "Ideal situation for someone" .)