What kind of solid is crystalline boron (B)?A.Metallic solidB.Network solidC.Ionic solidD.Molecular solid

To determine what kind of solid crystalline boron (B) is, we need to consider the bonding and structure of boron in its crystalline form.

1. Characterization of Boron: Boron is a metalloid and has unique bonding characteristics. In its crystalline form, it does not exhibit typical metallic or ionic behaviors.

2. Nature of Bonding: Crystalline boron forms strong covalent bonds with other boron atoms, resulting in a network structure. These strong covalent interactions create a rigid and stable three-dimensional arrangement.

3. Exclusion of Other Options:

   • Metallic Solid (Option A): Metallic solids typically have delocalized electrons and a lattice of metal cations; boron does not fit this description.
   • Ionic Solid (Option C): Ionic solids are formed from the electrostatic attraction between cations and anions; boron does not form such compounds in its crystalline state.
   • Molecular Solid (Option D): Molecular solids consist of discrete molecules held together by intermolecular forces; boron forms covalent networks rather than individual molecules.

Final Answer

Boron is classified as a B. Network solid.