Formation of a Precipitate

This set of vocabulary flashcards covers the definition of precipitates, the factors affecting their formation, and specific chemical reactions involving barium sulphate and lead iodide.

Precipitates

Insoluble ionic solid products of a reaction, formed when certain cations and anions combine in an aqueous solution.

Factors of Precipitate Formation

Variables that determine if a precipitate forms, including solution concentration and temperature (used for solutions such as buffers).

Crystalline solids

The structural form of solids produced in precipitate reactions, which can fall to the bottom of the solution or be suspended throughout the liquid.

Barium sulphate ($BaSO_4$)

An insoluble white substance, also known as a precipitate, formed by the reaction of barium chloride solution and sulphuric acid.

Barium Chloride and Sulphuric Acid Reaction

$$BaCl_2(aq) + H_2SO_4(aq) \rightarrow BaSO_4(s) + 2HCl(aq)$$

Lead iodide ($Pbl_2$)

A bright yellow precipitate formed from the reaction of lead nitrate and potassium iodide, which changes the colour of the colourless reaction mixture to yellow.

Lead Nitrate and Potassium Iodide Reaction

$$Pb(NO_3)_2(aq) + 2Kl(aq) \rightarrow Pbl_2(s) + 2KNO_3(aq)$$