Explodes, breaks open (6)
I believe the answer is:
bursts
This clue is a double definition.
'explodes' is the first definition.
('burst' can be a synonym of 'explode')
'breaks open' is the second definition.
('burst' can be a synonym of 'break open')
(Other definitions for bursts that I've seen before include "Explodes or ruptures" , "Explodes from inside pressure like balloon" , "Spurts" , "Breaks open suddenly" , "Explodes or breaks open" .)