Which of the following aqueous solutions
should form a precipitate with aqueous
Fe(NO3)3?
1. KNO3
2. KCl
3. K2SO4
4. KOH
KOH
To determine which of the given aqueous solutions will form a precipitate with Fe(NO3)3, we need to identify the possible insoluble compounds that can be formed when Fe(NO3)3 is mixed with each solution.
1. KNO3: Potassium nitrate (KNO3) is a soluble salt and will not form a precipitate with Fe(NO3)3.
2. KCl: Like KNO3, potassium chloride (KCl) is also a soluble salt and will not form a precipitate with Fe(NO3)3.
3. K2SO4: Potassium sulfate (K2SO4) is generally soluble, but when it is mixed with certain metal cations like Fe3+, it forms insoluble compounds called sulfates. Therefore, K2SO4 has the potential to form a precipitate with Fe(NO3)3.
4. KOH: Potassium hydroxide (KOH) is a strong base and not an ionic salt. When mixed with Fe(NO3)3, it will lead to the formation of a basic solution rather than a precipitate.
So, out of the given options, the only solution that could form a precipitate with aqueous Fe(NO3)3 is K2SO4.