Solubility Rules

ready to pour

Predict

before you pour

Swap the partners. These are the only two compounds that can form:

Work each one through the rules below, then pour to check.

AP table

1
Group 1 and ammoniummemorizeSalts of Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺ and NH₄⁺ are soluble.
2
Nitrate, chlorate, perchloratememorizeNO₃⁻, ClO₃⁻ and ClO₄⁻ salts are soluble.
3
AcetateCH₃COO⁻ salts are soluble. Silver acetate is only slightly soluble.
4
Chloride, bromide, iodideSoluble except with Ag⁺, Pb²⁺ and Hg₂²⁺.
5
SulfateSoluble except with Ba²⁺, Pb²⁺ and Sr²⁺. CaSO₄ and Ag₂SO₄ are slightly soluble.
6
HydroxideInsoluble except with Rule 1 cations, Ba²⁺ and Sr²⁺. Ca(OH)₂ is slightly soluble.
7
SulfideInsoluble except with Rule 1 cations and the Group 2 metals.
8
Carbonate, phosphate, sulfite, chromateInsoluble except with Rule 1 cations.

Rules 1 and 2 are the only ones you have to know by heart. Whenever the exam tests solubility, the rest of the table is given to you.