What type of solid will each of the following substances form? a. diamond e. KCl i. Ar b. PH3 f. quartz j. Cu c. H2 g. NH4NO3 k. C6H12O6 d. Mg h. SF2
The Correct Answer and Explanation is:
Here is the type of solid each substance will form:
a. Diamond – Covalent Network Solid
b. PH₃ – Molecular Solid
c. H₂ – Molecular Solid
d. Mg – Metallic Solid
e. KCl – Ionic Solid
f. Quartz (SiO₂) – Covalent Network Solid
g. NH₄NO₃ – Ionic Solid
h. SF₂ – Molecular Solid
i. Ar – Atomic Solid
j. Cu – Metallic Solid
k. C₆H₁₂O₆ (glucose) – Molecular Solid
Explanation
Solids are classified based on the nature of the particles that compose them and the types of forces holding those particles together. These classifications include molecular, ionic, metallic, covalent network, and atomic solids.
Covalent network solids like diamond and quartz consist of atoms connected by a continuous network of covalent bonds. Diamond is made entirely of carbon atoms bonded in a tetrahedral lattice, giving it extraordinary hardness. Quartz consists of silicon and oxygen atoms arranged in a rigid three-dimensional framework.
Molecular solids are composed of discrete molecules held together by intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonding. Substances like PH₃, H₂, SF₂, and glucose fall into this category. These solids tend to have low melting points and are often soft. Glucose, for example, forms a molecular solid due to strong hydrogen bonding between its hydroxyl groups.
Ionic solids like KCl and NH₄NO₃ are composed of positively and negatively charged ions held together by strong electrostatic forces. KCl consists of potassium and chloride ions in a crystal lattice. NH₄NO₃ has ammonium and nitrate ions, also forming a stable ionic structure.
Metallic solids such as magnesium and copper consist of metal cations surrounded by a “sea” of delocalized valence electrons. This structure accounts for their high electrical and thermal conductivity, malleability, and luster.
Atomic solids include noble gases like argon when solidified under low temperatures. These solids are held together by weak London dispersion forces and have very low melting points due to the absence of strong bonding between atoms.
Each type of solid has characteristic properties that arise from the nature and strength of the interactions between its building blocks.
