Upset critic and I get something caustic (6,4)

I believe the answer is:

nitric acid

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'something caustic' is the definition.
I can't judge whether this defines the answer.

'upset critic and i' is the wordplay.
'upset' indicates an anagram.
'critic'+'and'+'i'='criticandi'
'criticandi' is an anagram of 'NITRIC ACID'.

'get' acts as a link.

Can you help me to learn more?

(Other definitions for nitric acid that I've seen before include "dangerous stuff?" , "component of explosive" , "Corrosive liquid" .)

I've seen this clue in The Daily Express.

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