The salts can be prepared using three processes: filtration, titration and filtration+precipitation.
The process that uses a insoluble base that reacts with an acid to make a soluble salt is called filtration.
The processes that uses a insoluble base that reacts with an acid to make an insoluble salt are called filtration+precipitation.
Since the problem does not specify if the product of reaction is a soluble or insoluble salt, you can consider the following two reactions, one reaction produces a soluble salt, the other produces an insoluble salt, such that:
- copper oxide reacts with sulphuric acis to produce the soluble salt copper sulphate, with the following balanced chemical reaction:
`CuSO_4 + H_2SO4 -gt CuSO_4 + H_2O`
- lead oxide reacts with nitric acid to produce lead nitrate that reacts with aqueous iodide to produce lead iodide, with the following balanced chemical reactions:
`HNO3 + PbO (s) -gt Pb(NO3)2 + H2O`
`2 KI + Pb(NO3)2 -gt PbI2 + 2 KNO3`