L2 CHEM NOTES

Cation

The positively charged ion in a compound.

Anion

The negatively charged ion in a compound.

Precipitation reaction

A reaction where at least one of the products is insoluble, resulting in a solid precipitate.

Double displacement reaction

A reaction in which both products are soluble.

Ionic equation

An equation that shows the ions and their charges in a solution.

Spectator ions

Ions that do not participate in the reaction and remain unchanged on both sides.

Complex ions

Ions formed by a metal cation bonded to one or more ligands.

Ligand

An ion or molecule that donates a pair of electrons to a metal cation to form a complex.

Reagent

A substance or compound that is added to a system to bring about a chemical reaction.

Hydroxide precipitate

A solid formed when hydroxide ions react with certain metal cations.

Iron(II) hydroxide

A green precipitate formed when iron(II) ions react with hydroxide ions.

Dilute acids

Acids that are used to react with compounds to determine the presence of specific ions.

Barium sulfate

A white precipitate formed when barium ions react with sulfate ions.

Copper hydroxide

A blue precipitate that can dissolve in excess ammonia to form a complex ion.

Color reaction with reagents

Observing the color change of precipitates as a method for identifying cations.