9.2 solution mixed with solution in 1:1 molar ratio gives the test of ion but solution mixed with aqueous ammonia in 1:4 molar ratio does not give the test of ion. Explain why?
The major difference between both the compounds is that the first compound is a salt and the other one is a coordination compound. In case of double salt compounds (Mohr's salt), the compound breaks into its constituent ions when dissolved in water, therefore it gives a positive test for the presence of Fe+2. But in case of coordination compounds, they maintain their identity in both solid and dissolved state. Thus the individual property of each constituent is lost. And therefore it doesn't give a positive test for Cu+2.