Precipitation Reactions

A precipitation reaction refers to the formation of an insoluble ionic compound when two aqueous solutions are combined.

The reason water dissolves some ionic compounds is the attraction between the water and the cations/anions is stronger than the attraction between the cations and anions

Today we will learn the rules to identify if a solid will form when two aqueous solutions are mixed

Halides are chemical compounds that contain Halogens.

Halogens are group 17 elements; Fluorine, Chlorine, Bromine and Iodine

Halides are soluble in water EXCEPT

When they contain Silver (Ag⁺) and Lead (Pb²⁺)

Ionic compounds containing Sulfate are soluble with water EXCEPT

When they contain Stronium, Barium or Lead

Hydroxides are ionic compounds containing Hydroxide (OH^-). They are usually insoluble EXCEPT

When the contain Sodium, Ammonium, Potassium and Barium

*Notice that 3 of these are from SNAPE

These three are all the same

They are always insoluble EXCEPT

When they are mixed with Sodium, Potassium and Ammonium

*All three from SNAPE (so you don't need to remember)

You don't need to remember the solubility rules

Because you will have a handy solubility table

But the better you understand these rules, the better you will be at using the table