A diatomic molecule X undergoes ionization to form a cation ( X^+ ) and also gains an electron to form an anion ( X^- ). When X is ionized to X^+ , its bond length decreases and it becomes diamagnetic. When X gains an electron to form X^- , its bond length increases and it remains paramagnetic. Identify the molecule X .

Step-by-step solution

Analyze the given conditions: The molecule X must initially be paramagnetic, because forming X^- leaves it paramagnetic (as stated by "remains paramagnetic"). For N₂ and CO (14 electrons): Both are diamagnetic initially, which contradicts the condition. For O₂ (16 electrons): The bond order is 2 and it is paramagnetic (2 unpaired electrons). Its cation O₂^+ (15 electrons) has a bond order of 2.5 (bond length decreases) but has 1 unpaired electron, meaning it is still paramagnetic. This contradicts the condition tha