Properties of Ionic and Covalent Compounds

Ionic Compounds Representative Unit: Formula Unit Bond Formation: Transfer of one or more electrons between atoms Physical state: solid Melting Point: High Solubility: High in water Conductivity in solution: Good Conductor

Formula Unit Formula Unit: The lowest whole number ration of ions in an ionic compound Ex: NaCl is the formula unit for Sodium chloride Ratio is one Na to one Cl

Physical State of Ionic Compounds Most are crystalline solids at room temperature Large attractive forces result in a very stable structure (results in a high melting point)

Solubility of Ionic Compounds Highly soluble in water Ionic Compound dissociates into individual ions Free moving electrons conduct electric current

Properties of Covalent Compounds Representative Unit: Molecule Bond Formation: Sharing of electron pairs Physical State: solid, liquid, or gas Melting Point: low Solubility in water: low to high Conductivity in aqueous solution: poor

Covalent Compounds Formula Unit: Molecule Molecule: a neutral group of atoms joined together by covalent bonds

Bond Formation of Molecules Sharing of electron pairs

Melting Point of Covalent Compounds Melting is caused by the breaking of attractions between molecules Attraction between molecules are weak = low melting point

Solubility of Covalent Compounds Polar Compounds: dissolve in polar solutions Nonpolar Compounds: dissolve in nonpolar solutions “Like dissolves like”