Question

early chemists focused on answering questions.

Explanation:

Early chemists were mainly concerned with questions related to the composition, properties, and transformations of matter, often focusing on practical or descriptive aspects like identifying substances, their uses, and how they change (e.g., alchemists trying to turn base metals into gold, or understanding medicinal properties of substances). A common focus was "what" - what substances are, what their properties are, etc. So a key type of question they focused on was descriptive or "what" - related, like "what is this substance made of?" or "what happens when we mix these substances?".

Answer:

what (or descriptive, but "what" is a common fill - in here as early chemistry was about identifying and describing matter's composition, properties, etc.)