Answers
In the image, the particles are arranged in a hexagonal close pack structure. This kind of structuring can only take place in a solid system. Hence xenon is in solid state in the image.
Between atoms and molecules, different kinds of interactions are observed. One of the interactions that is found in case of nonpolar systems is known as London dispersion forces. It is a weak kind of interactions that arises when the electrons are arranged unsymetrically in the atoms or molecules.
In such cases, an instantaneous attraction takes place between the oppositely oriented dipoles. Because of such interactions, the nonpolar atoms or molecules can form liquids or solid at lower temperature.
Here because of this London dispersion force between the atoms, the xenon atoms form solid structure as shown in the image.
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