ineffective, ineffectual, unable, impuissant, Impotent
The antonym for the word emitted is absorbed.
The antonym for the word solution is problem or issue.
This depends somewhat upon context. Sometimes potency refers to male fertility. At other times it refers to power or strength. A potent drink has a high alcohol content and is therefore strong. A potent drug is very effective.
Cinders are hot ashes, there is no antonym for this word.
Consensual: relating to or involving consent
A close antonym would be shrinkage.
unsurprised
allows
enlarge
rejected.
plentiful
Current or present is the closest antonym for the word former.
probly like profitable
Joyous might be a good one
sell
Go or start or commence are antonyms of halt
INSIGNIFICANT?