Solubility products and supersaturation values for the hydroxides of copper and iron acting as precursor for FeOOH and CuO.

Precursor	K sp	S for end-pH 12
Cu(OH)2	2.20 × 10−20 [mol3 L−3]24	9.1 × 1013
Cu2(OH)3Cl	2.34 × 10−35 [mol6 L−6]25	5.2 × 1024
Fe(OH)3	2.79 × 10−39 [mol4 L−4]24	2.8 × 1031