## Chemistry and Chemical Reactivity (9th Edition)

a) $2\ Na^+, CO_3^{2-}$ b) $Cu^{2+}, SO_4^{2-}$ c) Insoluble. d) $Ba^{2+}, 2\ Br^{-}$
a) $2\ Na^+, CO_3^{2-}$ Sodium salts are almost always soluble. b) $Cu^{2+}, SO_4^{2-}$ Sulfates are usually soluble, copper (||)'s is not an exception. c) Insoluble. Sulfides are usually insoluble, and Nickel (||)'s is not an exception. d) $Ba^{2+}, 2\ Br^{-}$ Bromides are usually soluble, and barium's is not an exception.