Precipitation Reactions and Solubility Rules

Practice vocabulary flashcards based on the lecture notes on precipitation reactions, solubility rules, and equation types including molecular, ionic, and net ionic.

Precipitation Reaction

A chemical reaction that produces an insoluble solid that separates from solution.

Precipitate

An insoluble solid that forms as a result of a precipitation reaction.

Aqueous ($aq$)

A notation indicating that a substance is in solution, specifically for reactions occurring in water.

Cation

The positively charged ion that always comes first in the formula of an ionic compound.

Anion

The negatively charged ion that always comes second in the formula of an ionic compound.

Molecular Equation

A representation of a chemical reaction where the reactants and products are written as neutral formulas and the equation is balanced.

Ionic Equation

An equation where all reactants and products are broken apart into their individual cations and anions, except for the precipitate which remains intact.

Net Ionic Equation

The final form of a chemical equation that includes only those ions directly contributing to the formation of the precipitate.

Spectator Ions

Ions that appear in the ionic equation but do not participate in the formation of the precipitate and are cancelled out to form the net ionic equation.

Dissociate

The process of breaking apart an ionic compound into its component cations and anions when in an aqueous solution.

Solubility

The maximum amount of solute that will dissolve in a given quantity of solvent at a specific temperature.

Solute

The substance that is dissolved in a solvent to create a solution.

Solvent

The substance, such as water ($H_2O$), in which the solute is dissolved.

Alkali Metal Ions

Group 1 metal ions that make a compound soluble, meaning they do not typically form precipitates.

Halide

Anions formed from Group 7 elements that are generally soluble except when combined with silver ($Ag^+$), mercury ($Hg_2^{2+}$), or lead ($Pb^{2+}$).

Insoluble

A term used to describe a compound that does not dissolve in solution and acts as a precipitate.

Soluble

A term used to describe compounds that dissolve completely in aqueous solution.

Polyatomic Ion

A group of more than one atom carrying a charge, such as nitrate ($NO_3^-$) or phosphate ($PO_4^{3-}$), balanced as a single entity.

Solubility Rule

A set of guidelines used to identify whether an ionic compound is soluble or will form an insoluble precipitate.

Lead (II) Iodide ($PbI_2$)

A specific yellowish solid formed as a precipitate in the reaction between lead (II) nitrate and potassium iodide.

Nitrate ($NO_3^-$)

A common polyatomic ion with a charge of $-1$ that is always found in soluble compounds according to the solubility rules.

Sulfate ($SO_4^{2-}$)

A polyatomic ion that forms precipitates when combined with specific cations like calcium ($Ca^{2+}$), silver ($Ag^{+}$), or lead ($Pb^{2+}$).

Calcium Carbonate ($CaCO_3$)

An ionic compound classified as insoluble derived from the combination of the calcium cation and the carbonate anion.

Silver Sulfate ($Ag_2SO_4$)

A compound identified as insoluble due to the specific solubility exception involving the silver cation paired with sulfate.

Sodium Phosphate ($Na_3PO_4$)

A soluble compound where the sodium cation takes preference over the phosphate anion, making it aqueous rather than a precipitate.