Extracting energy, continue to study gas (5)
I believe the answer is:
radon
'gas' is the definition.
(I've seen this before)
'extracting energy continue to study' is the wordplay.
'extracting' suggests deleting specific letters.
'energy' becomes 'go' (go can mean energy or enthusiasm).
'continue' becomes 'go on' (synonyms).
'to' is a charade indicator (letters next to each other) (I've seen this in other clues).
'study' becomes 'rad' (I can't explain this - if you can you should believe this answer much more).
'goon' with 'go' removed is 'on'.
'on' after 'rad' is 'RADON'.
Can you help me to learn more?
(Other definitions for radon that I've seen before include "A radioactive gas, symbol Rn" , "hazardous substance" , "Radioactive gas, linked to granite" , "Gaseous element, Rn" , "gets no reaction" .)