Structure and Properties of Bonds

Ionic Compounds Crystalline - Arranged in crystal lattices with each ion surrounded by many oppositely charged ions. Brittle -When force is applied it causes like charges to align causing it to break.

Ionic Compounds High Melting/Boiling Points – Melting/Boiling involves breaking bonds between ions which takes a lot of energy Solubility –Soluble in water as the charged ions are attracted to the partial charges of polar water molecules

Ionic Compounds Electrical Conductivity – Solids are not conductive as the ions are locked in place, however when molten or dissolved in water the ions can move easily and so are very conductive.

Covalent Compound Soft and Squishy – There are only bonds present inside the molecules, not between them, and so therefore covalent compounds are a lot more flexible rather than hard.

Covalent Compound Low Melting/Boiling Points – Melting only involves separating the molecules from each other where there are no bonds, so it melts/boils more easily. Solubility – Most do not dissolve in water as most are non-polar and so are not attracted to the charges in water.

Covalent Compound Electrical Conductivity – Even when the molecules can move around as a liquid or dissolved in a liquid, the molecules don’t have charges and so make poor conductors.

Metallic Bonds + + + + + + + + + + + + Free-floating – Valence electrons do not stay around any one atom as metals hold them very weakly, instead the cations float in a sea of electrons. Malleable – hammered into shape Ductile draw into wire are both related to this as the free floating electrons allow the cations to slide past like ball bearings in oil. + + + + + + + + + + + +

Metallic Bonds Conductivity – Metals are very conductive, this is due to the sea of electrons. As the electrons are not attached to a cation in particular, they can move back and forth with great ease leading to the high conductivity.

Metallic Bonds Alloy – mixture of 2 or more elements of which at least 1 is a metal created by mixing the melted ingredients together and allowing to cool. Often have properties superior to the pure elements. Brass Bronze Steel