Question
Predicting precipitationComplete the table below by deciding whether a precipitate forms when aqueous solutions A and B are mixed. If a precipitate forms, enter its empirical formula in the last column.1. Potassium sulfide + lead(II) nitrate2. Barium nitrate + sodium acetate3. Iron(II) chloride + nickel(II) sulfateFor each row, state Yes or No and, when Yes, give the precipitate's empirical formula.
Answers
| Solution A | Solution B | Precipitate? | Empirical formula |
|---|---|---|---|
| Potassium sulfide | Lead(II) nitrate | Yes | |
| Barium nitrate | Sodium acetate | No | — |
| Iron(II) chloride | Nickel(II) sulfate | No | — |
1. Potassium sulfide and lead(II) nitrate
Exchanging ions produces lead(II) sulfide and potassium nitrate. Lead(II) sulfide is insoluble under the standard solubility guidelines:
Therefore a precipitate forms, and its empirical formula is .
2. Barium nitrate and sodium acetate
The possible products are barium acetate and sodium nitrate. Acetate salts and nitrate salts are soluble under the standard guidelines, so no precipitate is predicted.
3. Iron(II) chloride and nickel(II) sulfate
The possible products are iron(II) sulfate and nickel(II) chloride. Neither is an insoluble exception in the standard sulfate and chloride rules, so no precipitate is predicted.
Evidence boundary
The predictions apply to the three aqueous pairs in the locked question version and use the standard qualitative solubility guidelines expected for introductory chemistry. They do not model unusual concentrations, temperature-dependent solubility, complex-ion formation, or kinetic effects not specified in the prompt.
Sources
These references support the concepts and methods used in the explanation above.