Which solids are held together by intermolecular forces rather than covalent bonds?

Which solids are held together by intermolecular forces rather than covalent bonds?

• A. Ionic solids
• B. Covalent network solids
• C. Molecular solids
• D. Metallic solids

Answer: (C)

Molecular solids are held together by intermolecular forces rather than covalent bonds. In these solids, the repeating units are whole molecules, and the forces tying them together are weaker interactions such as London dispersion, dipole-dipole, and sometimes hydrogen bonding. Because these inter-molecular attractions are relatively weak compared to covalent bonds, molecular solids typically have lower melting points, can be softer, and often do not conduct electricity well. In contrast, ionic solids are held together by strong electrostatic forces between ions, covalent network solids (like diamond or quartz) are bonded by a continuous network of covalent bonds throughout the structure, and metallic solids are held together by metallic bonds with a lattice of positive ions in a sea of delocalized electrons. Examples of molecular solids include ice and sugar crystals.

Molecular solids are held together by intermolecular forces rather than covalent bonds. In these solids, the repeating units are whole molecules, and the forces tying them together are weaker interactions such as London dispersion, dipole-dipole, and sometimes hydrogen bonding. Because these inter-molecular attractions are relatively weak compared to covalent bonds, molecular solids typically have lower melting points, can be softer, and often do not conduct electricity well.

In contrast, ionic solids are held together by strong electrostatic forces between ions, covalent network solids (like diamond or quartz) are bonded by a continuous network of covalent bonds throughout the structure, and metallic solids are held together by metallic bonds with a lattice of positive ions in a sea of delocalized electrons. Examples of molecular solids include ice and sugar crystals.