Lab Analysis: Identifying Solids

Vocabulary practice flashcards covering the properties, intermolecular forces, bonding types, and identification criteria of metallic, covalent network, polar molecular, ionic, and non-polar molecular solids.

Metallic Solid (Sample #1)

A solid identified by its shiny lustre, insolubility in water, high melting point, and ability to conduct electricity in the solid state due to mobile delocalised valence electrons.

Delocalised Valence Electrons

Valence electrons that are free to move throughout the structure of a metallic solid, giving metals their lustre and allowing electrical charge to flow.

Covalent Network Solid (Sample #2)

A solid consisting of atoms connected by strong covalent bonds throughout a large continuous network, resulting in water insolubility and a high melting point.

Diamond

A covalent network solid composed of carbon atoms joined by strong covalent bonds in a three-dimensional network, creating an extremely hard material used for cutting and drilling tools.

Polar Molecular Solid (Sample #3)

A solid that does not conduct electricity as a solid, is soluble in water, and has a moderate melting point (melting in approximately $1.25\text{ minutes}$), held together by intermolecular forces that are weaker than ionic or covalent network bonds.

Ionic Solid (Sample #4)

A solid held together by strong electrostatic attractions between oppositely charged ions, characterized by a high melting point, non-conductivity as a solid, and high conductivity ($3145\,\mu\text{S/cm}$) when dissolved in water.

Mobile Ions

Charged particles that are locked in fixed positions in an ionic solid but become free to move and carry electrical current once the solid is dissolved in water.

Ion-Dipole Forces

Attractive forces between the positive and negative ions of an ionic compound and the oppositely charged partial ends of polar water molecules, which help separate ions during dissolving.

"Like Dissolves Like"

A chemical principle stating that polar substances tend to dissolve in polar solvents such as water, while non-polar substances generally do not.

Non-Polar Molecular Solid (Sample #5)

A soft, non-conducting solid that is insoluble in water and exhibits a very low melting point (melting in approximately $6\text{ seconds}$) because it is held together primarily by weak London dispersion forces.

London Dispersion Forces

Relatively weak intermolecular forces holding non-polar molecules together, which require only a small amount of energy to overcome, resulting in rapid melting.

Electrical Wiring Application

A real-world application of metallic solids utilizing their high electrical conductivity, which is made possible by the presence of free-flowing delocalised electrons.