What's the plural form of acenaphthoquinone? Here's the word you're looking for.
Answer
The noun acenaphthoquinone can be countable or uncountable.
In more general, commonly used, contexts, the plural form will also be acenaphthoquinone.
However, in more specific contexts, the plural form can also be acenaphthoquinones e.g. in reference to various types of acenaphthoquinones
or a collection of acenaphthoquinones.