A laboratory instructor gives you a test tube containing Ag+ ,Ba 2+ , and Cu 2+ ions. Devise a reaction scheme that would allow you to selectively precipitate each of these ions. Write a balanced net ionic equation for each precipitation reaction.
Ag^+ + Cl^- ==> AgCl(s)
Ba^2+ + SO4^2- ==> BaSO4(s)
Cu^2+ + 2OH^- ==> Cu(OH)2(s)
Add Cl^-, filter AgCl. Treat with Na2SO4 and filter BaSO4. Add NaOH. Filter Cu(OH)2.
thank you!
To selectively precipitate each of the ions, you can perform the following series of reactions:
1. To precipitate Ag+ ions:
- Add a few drops of dilute hydrochloric acid (HCl) to the test tube.
- Ag+ ions will react with chloride ions from HCl to form an insoluble white precipitate of silver chloride (AgCl).
- The balanced net ionic equation for this reaction is:
Ag+ (aq) + Cl- (aq) -> AgCl (s)
2. To precipitate Ba2+ ions:
- After removing any precipitate formed in the previous step, add a few drops of sulfuric acid (H2SO4) to the test tube.
- Ba2+ ions will react with sulfate ions from H2SO4 to form an insoluble white precipitate of barium sulfate (BaSO4).
- The balanced net ionic equation for this reaction is:
Ba2+ (aq) + SO4 2- (aq) -> BaSO4 (s)
3. To precipitate Cu2+ ions:
- After removing any precipitate formed in the previous step, add a few drops of sodium hydroxide (NaOH) solution to the test tube.
- Cu2+ ions will react with hydroxide ions from NaOH to form a blue precipitate of copper hydroxide (Cu(OH)2).
- The balanced net ionic equation for this reaction is:
Cu2+ (aq) + 2 OH- (aq) -> Cu(OH)2 (s)
By following this reaction scheme, you can selectively precipitate Ag+, Ba2+, and Cu2+ ions in the test tube.
To selectively precipitate each of the Ag+, Ba2+, and Cu2+ ions, you can use various reagents that form insoluble salts with each cation. The solubility rules can guide you in identifying the appropriate reagents. Here's a reaction scheme to selectively precipitate each ion:
1. To precipitate Ag+ ions:
- Add a few drops of dilute nitric acid (HNO3) to the test tube to acidify the solution.
- Add a few drops of silver nitrate (AgNO3) solution.
- Ag+ ions react with Cl- or Br- ions to form insoluble silver chloride (AgCl) or silver bromide (AgBr):
Ag+(aq) + Cl-(aq) → AgCl(s) or
Ag+(aq) + Br-(aq) → AgBr(s)
- The balanced net ionic equation for the precipitation reaction can be written as:
Ag+(aq) + Cl-(aq) → AgCl(s) or
Ag+(aq) + Br-(aq) → AgBr(s)
2. To precipitate Ba2+ ions:
- Add a few drops of dilute sulfuric acid (H2SO4) to the test tube to acidify the solution.
- Add a few drops of sodium sulfate (Na2SO4) solution.
- Ba2+ ions react with sulfate ions (SO42-) to form insoluble barium sulfate (BaSO4):
Ba2+(aq) + SO42-(aq) → BaSO4(s)
- The balanced net ionic equation for the precipitation reaction can be written as:
Ba2+(aq) + SO42-(aq) → BaSO4(s)
3. To precipitate Cu2+ ions:
- Add a few drops of sodium hydroxide (NaOH) solution to the test tube.
- Cu2+ ions react with hydroxide ions (OH-) to form insoluble copper(II) hydroxide (Cu(OH)2):
Cu2+(aq) + 2OH-(aq) → Cu(OH)2(s)
- The balanced net ionic equation for the precipitation reaction can be written as:
Cu2+(aq) + 2OH-(aq) → Cu(OH)2(s)
By following this reaction scheme, you will selectively precipitate Ag+, Ba2+, and Cu2+ ions into their respective insoluble salts.