Net Ionic Equations
#1: Precipitation Reactions
Name:
Instructions: Write balanced net ionic equations for the following
experimental conditions. In every instance, a reaction occurs. Make certain that spectator ions, if present in a reaction, do not appear in your final answer. Draw a box around your final answer. Everything inside the box will be graded; everything outside the box will be disregarded. If a box is not present, you will receive no credit for your answer.
Score: 56×2 Helpful Hints for Writing Precipitation Reactions
Precipitation reactions typically involve two ionic salts exchanging their anions:
Example Problem: Solutions of silver nitrate and sodium chloride are poured together.
Full Equation: AgNO3(aq) + NaCl(aq) AgCl(s) + NaNO3(aq)
The nitrate and chloride anions swap
Soluble salts separate into cations and anions when placed in water. Some of the reagent ions will come together to form an insoluble salt (a precipitate); other ions may not react (change form) and are hence identified as spectator ions. Write out a total ionic equation to show all of the chemical species present in a reaction, then eliminate the spectator ions to arrive at your final NIE answer.
Total Ag+(aq) + NO3-(aq) + Na+(aq) + Cl-(aq) AgCl(s) + Na+(aq) + Cl-(aq) Ionic Equation
NIE: Ag+ + Cl- AgCl
You do not need to include the states of the chemicals (s), (l), (g), or (aq) in your final answer.
If the problem says that a reagent is a solid, liquid or gas, DO NOT split it up into ions on the reagent side of the arrow. DO NOT give it a charge, because it is charge-neutral!
DO NOT ASSUME that if you only have one chloride in a compound on the reagent side of an arrow, you can only have one chloride in a product on the opposite side of the
arrow. Make sure that precipitates are written in a way that makes them charge-neutral.
Problems:
1. Solutions of copper(II) chloride and sodium hydroxide are mixed.
2. Solutions of manganese(II) sulfate and ammonium sulfide are mixed.
3. An excess of sodium hydroxide solution is added to a solution of magnesium nitrate.
4. A solution of copper(II) sulfate is added to a solution of barium hydroxide.
5. Solutions of potassium phosphate and zinc nitrate are mixed.
6. Hydrogen sulfide gas is bubbled into a solution of nickel(II) nitrate.
7. Solutions of cadmium sulfate and sodium phosphate are mixed.
8. Solutions of silver nitrate and lithium bromide are mixed.
9. Solutions of cobalt(II) nitrate and sodium hydroxide are mixed.
10. A solution of nickel(II) chloride is added to a solution of sodium sulfide.
11. Solutions of mercury(I) nitrate and zirconium(IV) bromide are mixed.
12. Lead(II) chlorate and and nickel(II) bromide solutions are mixed.
13. Aluminum chloride and sodium phosphate solutions are mixed.
14. Hydrogen sulfide gas is bubbled into a solution of mercury(II) chloride.
