Question

question 3 a molecule consists of two or more atoms
by covalent bonds.

Explanation:

The sentence "A molecule consists of two or more atoms ____ by covalent bonds" requires a word that shows the atoms are joined or bonded. The correct word here is "bonded" or "joined", but in the context of the sentence structure (passive voice), the appropriate verb form is "bonded" (or "held together", but the most fitting term for the blank is "bonded" or more precisely, the correct term is "bonded" or "linked". Wait, actually, the correct term is "bonded" or more accurately, the word is "bonded" or "held" but the standard term here is "bonded" or "linked". Wait, the correct answer is "bonded" or more precisely, the word is "bonded" (the sentence is "A molecule consists of two or more atoms bonded by covalent bonds."). Wait, actually, the correct term is "bonded" (as in the atoms are bonded together by covalent bonds). So the blank should be filled with "bonded" (or "held together", but the most appropriate single word here is "bonded").

Answer:

bonded