1. Covalent Bonding: Covalent compounds are formed when atoms share electrons in their outermost orbitals to achieve a stable electron configuration.
2. Molecular Structure: Covalent compounds exist as discrete molecules, unlike ionic compounds that form crystal lattices.
3. Electrical Conductivity: Covalent compounds generally do not conduct electricity in the solid state because their electrons are localized and not free to move.
4. Melting and Boiling Points: Covalent compounds typically have lower melting and boiling points compared to ionic compounds due to weaker intermolecular forces between molecules.
5. Solubility: Covalent compounds can be either soluble or insoluble in water depending on their polarity. Polar covalent compounds, which have a partial charge separation, tend to be soluble in water, while nonpolar covalent compounds are immiscible with water.
6. Chemical Reactivity: Covalent compounds are generally less reactive than ionic compounds because the sharing of electrons creates a more stable configuration.
7. Bond Strength: Covalent bonds are typically stronger than hydrogen bonds and van der Waals forces, but weaker than ionic bonds. The strength of a covalent bond depends on the number of electron pairs shared between atoms.
8. Stability: Covalent compounds are generally more stable than ionic compounds in nonpolar solvents because they do not undergo dissociation.
9. Flammability: Nonpolar covalent compounds, such as hydrocarbons, are generally flammable due to the presence of carbon-carbon bonds that readily react with oxygen.
10. Hardness and Brittleness: Covalent compounds tend to be softer and more brittle than ionic compounds because the covalent bonds between atoms are directional and rigid.
11. Vapor Pressure: Covalent compounds have higher vapor pressures than ionic compounds because the intermolecular forces between molecules are weaker.
12. Volatility: Covalent compounds are often more volatile than ionic compounds because they can readily vaporize due to their lower intermolecular forces.
13. Polymorphism: Covalent compounds can exhibit polymorphism, where different crystal structures can exist for the same compound under different conditions.
