Final answer:
The relevant experiments for the student's investigation of intermolecular forces would not include tests for metallic bonding, as the substances (salt, sugar, mothballs) do not contain metallic bonds. The behavior of these substances in polar solvents like water can reflect their intermolecular forces, which differ between ionic, polar covalent, and nonpolar covalent compounds.
Step-by-step explanation:
The student's investigation focuses on the comparison between the strength of intermolecular interactions in ionic and covalent substances. Since salt (NaCl) forms ionic bonds, sugar (sucrose) contains polar covalent bonds, and moth balls (typically naphthalene) have nonpolar covalent bonds, observing their behavior in various conditions can reflect on their intermolecular forces. One of the tests that would not be relevant to this experiment would likely be any test that measures the strength of metallic bonds, as metallic bonding is not present in any of the substances being investigated.
Considering the periodic table positioning and the kinds of atoms involved, covalent bonding occurs between nonmetals while ionic bonding usually involves a metal and a nonmetal. The solubility of these compounds in polar solvents like water also indicates the nature of their intermolecular forces, with ionic and polar compounds generally being soluble, and nonpolar compounds like moth balls being insoluble. It is worth noting that the strength of the intermolecular forces is different from the strength of chemical bonds within a molecule. For instance, ionic bonds are strong within a compound but may lead to weaker intermolecular interactions in a solid compared to covalently bonded molecules.