What are the properties of ionic compounds compared to covalent compounds?
Answers:
Ionic and covalent compounds exhibit distinct properties due to the differences in the nature of the bonding between their constituent atoms. Here’s a comparison of their properties:
Ionic Compounds
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Formation: Ionic compounds are formed by the transfer of electrons from one atom (usually a metal) to another (usually a non-metal), resulting in the formation of positive (cation) and negative (anion) ions.
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Structure: They typically form crystalline lattice structures, which maximize the attraction between the oppositely charged ions.
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State at Room Temperature: Most ionic compounds are solid at room temperature.
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Melting and Boiling Points: They generally have high melting and boiling points due to the strong electrostatic forces (ionic bonds) between the ions.
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Solubility: Many ionic compounds are soluble in water and other polar solvents but are insoluble in nonpolar solvents.
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Electrical Conductivity: Ionic compounds conduct electricity when dissolved in water or molten because the ions are free to move. In solid form, they do not conduct electricity.
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Brittleness: Ionic compounds are often brittle and tend to shatter when force is applied, due to the displacement of ions in the lattice structure, causing like charges to repel.
Covalent Compounds
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Formation: Covalent compounds are formed by the sharing of electrons between atoms (usually non-metals), leading to the formation of molecules.
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Structure: They can exist as individual molecules (e.g., water, CO₂) or in extended networks (e.g., diamond, silicon dioxide), depending on the type of covalent bond.
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State at Room Temperature: Covalent compounds can be gases, liquids, or solids at room temperature.
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Melting and Boiling Points: Covalent compounds generally have lower melting and boiling points compared to ionic compounds, though some (like diamond) have very high melting points due to strong covalent networks.
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Solubility: Many covalent compounds are soluble in nonpolar solvents but may be insoluble or poorly soluble in water.
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Electrical Conductivity: Covalent compounds typically do not conduct electricity, as they do not have charged particles that are free to move.
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Malleability and Ductility: Covalent compounds tend to be more flexible and can be malleable, depending on their structure.
Summary
In summary, ionic compounds are characterized by high melting and boiling points, solubility in water, and electrical conductivity in solution, leading to a crystalline structure and brittleness. In contrast, covalent compounds have variable states, lower melting and boiling points, poor conductivity, and can be flexible or brittle, depending on their specific molecular structures.
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