Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: orgo814 on March 14, 2012, 10:57:49 PM
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Can anyone help me differentiate between network solids and molecular solids? I know what they are but how can I tell by looking at a molecule whether it's a network or molecular solid? Is it really just allotropes of carbon and silicon molecules which are network solids? Any help is appreciated, thank you.
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Correct me if I'm wrong but aren't network solids simply ionic lattices and molecular solids formed from covalent bonds?
For example, a NaF lattice is a network solid because NaF is ionic, and a diamond is a molecular solid because it's merely a bunch of Carbon atoms bonded covalently.
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No, a network solid is an extensive network of covalent bonds.
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Molecular solid: think ice. There are covalent bonds present, but they're within a molecule, not between the molecules. What holds the molecule together are dispersion forces, dipole-dipole interactions or hydrogen bonds.
Covalent network solid: Think diamond. All of the carbon atoms in the entire substance are covalently bonded, forming a big network. Technically, a diamond is like one big molecule.
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I know what they are but how can I tell by looking at a molecule whether it's a network or molecular solid?
If you are looking at a drawing of a molecule, it is very simple. A network solid is not composed of separate molecules, but rather it is one gigantic molecule. Therefore, there should be no set drawing of a "molecule" of a network solid.