Answer
See answer below.
Work Step by Step
a) Soluble:
Copper (||) nitrate $Cu(NO_3)_2$
Copper (||) chlorate $Cu(ClO_3)_2$
Insoluble:
Copper (||) carbonate $CuCO_3$
Copper (||) sulfide $CuS$
b) Soluble:
Barium nitrate $Ba(NO_3)_2$
Barium chlorate $Ba(ClO_3)_2$
Insoluble:
Barium carbonate $BaCO_3$
Barium sulfide $BaS$
