List the formulas of three soluble bromide salts and three insoluble bromide salts. Do the same exercise for sulfate salts, hydroxide salts, and phosphate salts (list three soluble salts and three insoluble salts). List the formulas for six insoluble \(\mathrm{Pb}^{2+}\) salts and one soluble \(\mathrm{Pb}^{2+}\) salt.

Soluble bromide salts: \(\mathrm{NaBr}\), \(\mathrm{KBr}\), \(\mathrm{HBr}\); Insoluble bromide salts: \(\mathrm{AgBr}\), \(\mathrm{PbBr_2}\), \(\mathrm{Hg_2Br_2}\). Soluble sulfate salts: \(\mathrm{Na_2SO_4}\), \(\mathrm{K_2SO_4}\), \(\mathrm{CaSO_4}\); Insoluble sulfate salts: \(\mathrm{BaSO_4}\), \(\mathrm{PbSO_4}\), \(\mathrm{SrSO_4}\). Soluble hydroxide salts: \(\mathrm{NaOH}\), \(\mathrm{KOH}\), \(\mathrm{Ba(OH)_2}\); Insoluble hydroxide salts: \(\mathrm{Ca(OH)_2}\), \(\mathrm{Mg(OH)_2}\), \(\mathrm{Al(OH)_3}\). Soluble phosphate salts: \(\mathrm{Na_3PO_4}\), \(\mathrm{K_3PO_4}\), \(\mathrm{(NH_4)_3PO_4}\); Insoluble phosphate salts: \(\mathrm{Ca_3(PO_4)_2}\), \(\mathrm{Mg_3(PO_4)_2}\), \(\mathrm{AlPO_4}\). Insoluble \(\mathrm{Pb}^{2+}\) salts: \(\mathrm{PbCl_2}\), \(\mathrm{PbBr_2}\), \(\mathrm{PbI_2}\), \(\mathrm{PbSO_4}\), \(\mathrm{PbCO_3}\), \(\mathrm{PbCrO_4}\); Soluble \(\mathrm{Pb}^{2+}\) salt: \(\mathrm{Pb(NO_3)_2}\).