We have to determine if the given compound is soluble or insoluble in water.
The given compound is copper (II) hydroxide, . According to the solubility rules the hydroxides of all metal ions are insoluble except that of ammonium and the alkali metal ions. So copper(II) hydroxide will be insoluble in water. In aqueous solution, copper (II) hydroxide would exist as a sparingly soluble compound in which the undissociated compound remains in equilibrium with the ions and . The equilibrium would remain mostly towards undissociated form.
The pair of both compounds that have the same empirical formula are C6H12O6 and HC2H3O2. The answer is letter D. <span>H2O and H2O2, BaSO4 and BaSO3 and FeO and Fe2O3 do not have the same empirical formula.</span>