Final answer:
Option D: The molecule that is paramagnetic among the given options is N2^2+ because it has unpaired electrons due to the removal of two electrons compared to N2, resulting in a molecular orbital configuration with unpaired electrons.
Step-by-step explanation:
To determine which one of the listed molecules is paramagnetic, we need to understand the molecular orbital configurations and the presence of any unpaired electrons. A paramagnetic molecule is one that is attracted to magnetic fields due to these unpaired electrons, while a diamagnetic molecule, which has all electrons paired and is slightly repelled by a magnetic field, contains no unpaired electrons.
Let's look at the given options:
- Li2 is diamagnetic because it has a bond order of 1 and all electrons are paired.
- C2, also known as dicarbon, is also diamagnetic because it has two unpaired electrons but they are paired when the molecule is formed.
- N2 (N2, N2^2-, N2^2+) is naturally diamagnetic as it has no unpaired electrons.
- C2^2- has two extra electrons compared to C2, which means it has a pair of electrons that were unpaired in C2 effectively paired now, making it diamagnetic.
- N2^2+ has two fewer electrons than N2, creating unpaired electrons in its molecular orbital configuration. Therefore, N2^2+ is the molecule predicted to be paramagnetic.
According to molecular orbital theory, N2^2+ is the correct answer to which molecule is paramagnetic among the options provided.