Molecular solids are one of the four major types of solids you need to know about in AP chemistry. The others are ionic, metallic, and covalent network solids. Watch a video on the 🎥 structure of solids for additional help.
The Basics ⚛️
- Molecular solids are made of molecules or atoms held together by intermolecular forces, not covalent bonds.- Learn more through this study guide on Intramolecular Force and Potential Energy
- Take ice, for example.
- Sure, each individual molecule is held together by covalent bonds, but the actual solid is created by hydrogen bonds connecting the molecules to each other.
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Source: chemguide
Properties
- Intermolecular forces are weaker than ionic or covalent bonds, so molecular solids are relatively soft and flexible.
- This also means they tend to have low melting points.
- They do not conduct electricity because electrons are localized within individual molecules.
- Polar molecular solids, like sugar, will be soluble in water.
- Keep in mind that the individual molecules don't break apart, only the intermolecular forces do!