See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1 - Identify the structure: The image shows two benzene rings (each a six-membered aromatic ring with alternating double bonds) directly connected to each other by a single C-C bond. Step 2 - Apply IUPAC/common nomenclature: When two benzene (phenyl) rings are joined by a single bond, the resulting compound is named biphenyl. The prefix 'bi' indicates two identical units, and 'phenyl' refers to the benzene-derived ring system. Step 3 - Confirm: Biphenyl has the molecular formula C12H10, consisting of two phenyl groups bonded together. There are no substituents, no heteroatoms, and no fused rings — just two separate benzene rings connected at one carbon each. No other name (e.g., diphenyl is an older synonym, but biphenyl is the accepted IUPAC name) better fits this structure. Therefore, the correct answer is biphenyl.