Consisting of various kinds of arsenic, classified (8)
I believe the answer is:
assorted
'consisting of various kinds' is the definition.
I can't judge whether this definition defines the answer.
'arsenic classified' is the wordplay.
'arsenic' becomes 'As' (As is the chemical symbol for arsenic).
'classified' becomes 'sorted' ('sort' can be a synonym of 'classify').
'as'+'sorted'='ASSORTED'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for assorted that I've seen before include "Mixed" , "like some chocolates" , "Containing various different kinds" , "Odd-shaped" , "Rod's seat (anag)" .)