Paramagnetic Compound

To identify the paramagnetic compound among the given options, we need to understand the concept of paramagnetism and analyze each compound.

Paramagnetism:
Paramagnetism is a property exhibited by certain substances that are weakly attracted to an external magnetic field. This attraction arises due to the presence of unpaired electrons in the compound's molecular or atomic orbitals.

Analysis of Given Compounds:

a) Na2O2:
Sodium peroxide (Na2O2) is an ionic compound consisting of sodium cations (Na+) and peroxide anions (O2²⁻). Each oxygen atom has a -1 oxidation state, resulting in a total charge of -2 for the peroxide ion. In this compound, all electrons are paired, and there are no unpaired electrons. Therefore, Na2O2 is diamagnetic, not paramagnetic.

b) O3:
Ozone (O3) is a triatomic molecule consisting of three oxygen atoms. Each oxygen atom in the ozone molecule has two paired electrons and one unpaired electron. The presence of unpaired electrons makes ozone paramagnetic.

c) N2O:
Nitrous oxide (N2O) is a linear molecule consisting of two nitrogen atoms and one oxygen atom. Both nitrogen and oxygen atoms have paired electrons, and there are no unpaired electrons in this compound. Therefore, N2O is diamagnetic, not paramagnetic.

d) KO2:
Potassium superoxide (KO2) is an ionic compound consisting of potassium cations (K+) and superoxide anions (O2⁻). The superoxide ion has one unpaired electron, resulting in paramagnetic behavior for KO2.

Conclusion:
Among the given compounds, only KO2 is paramagnetic due to the presence of unpaired electrons in the superoxide ion.