What is the Difference Between Molecular Solid and Covalent Network Solid?

The main difference between molecular solids and covalent network solids lies in the nature of the bonding and the properties that result from these bonds.

Molecular Solids:

Held together by Van der Waals forces, such as London dispersion forces.
Relatively soft materials.
Lower melting points compared to covalent network solids.
Electrical insulators.
Examples include water ice and organic molecular solids.

Covalent Network Solids:

Held together by covalent bonding, forming a continuous network of chemical bonds.
Very hard materials.
High melting points due to the strength of the covalent bonds.
Low electrical conductivity at the liquid state and the solid state, depending on the composition.
Examples include diamond and silica.

In summary, molecular solids are relatively soft and have lower melting points, while covalent network solids are hard and have high melting points. Molecular solids are electrical insulators, whereas covalent network solids can have varying electrical conductivity depending on the specific composition.

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What is the Difference Between Molecular Solid and Covalent Network Solid?

Comparative Table: Molecular Solid vs Covalent Network Solid

Here is a table comparing molecular solids and covalent network solids:

Property	Molecular Solids	Covalent Network Solids
Definition	Molecular solids are made from individual separate molecules held together by intermolecular forces.	Covalent network solids are formed by networks or chains of atoms or molecules held together by covalent bonds, creating a single giant molecule or a continuous network of chemical bonds.
Structure	Molecular solids have a structure where each molecule is surrounded by other molecules, with intermolecular forces holding them together.	Covalent network solids have a continuous network of covalent bonds, where all atoms are covalently bonded together in a three-dimensional structure.
Examples	Examples of molecular solids include dry ice (CO₂) and naphthalene.	Examples of covalent network solids include diamond, silica, and silicon carbide.
Melting Point	Molecular solids generally have lower melting points, as the intermolecular forces are weaker than covalent bonds.	Covalent network solids have high melting points due to the strength of the covalent bonds.
Hardness	Molecular solids are typically soft or at least not as hard as covalent network solids.	Covalent network solids are usually hard and rigid, or soft in the case of two-dimensional networks like graphite.

In summary, molecular solids are composed of individual molecules held together by intermolecular forces, while covalent network solids are formed by networks or chains of atoms or molecules held together by covalent bonds. Covalent network solids have a continuous network structure, higher melting points, and are usually harder than molecular solids.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.