An unlabeled bottle containing a solution was found in the lab. It contains one of the following: AgNo3, CaCl2, or Al2(SO4)3. Describe how you would test the solution to determine which solution it is. Include equations in your answer.
To determine which solution is present in the unlabeled bottle, you can perform a series of tests using some chemicals that will react differently with each solution. Here's a step-by-step guide on how to determine the identity of the solution:
Note: It is essential to work in a well-ventilated area, wear appropriate safety goggles, gloves, and follow all laboratory safety protocols.
1. Test for chloride ions (Cl^-):
- Add a few drops of the solution to a test tube.
- Add a small amount of dilute silver nitrate (AgNO3) solution.
- Observe the formation of a white precipitate if chloride ions are present.
- The equation for this reaction is: AgNO3(aq) + Cl^-(aq) → AgCl(s) + NO3^-(aq)
2. Test for sulfate ions (SO4^2-):
- Add a few drops of the solution to a test tube.
- Add a small amount of dilute barium chloride (BaCl2) solution.
- Observe the formation of a white precipitate if sulfate ions are present.
- The equation for this reaction is: BaCl2(aq) + SO4^2-(aq) → BaSO4(s) + 2Cl^-(aq)
3. If both tests above are negative, it indicates that the solution does not contain chloride or sulfate ions, which means it could be calcium ions (Ca^2+) or silver ions (Ag^+).
4. Test for calcium ions (Ca^2+):
- Add a few drops of the solution to a test tube.
- Add a small amount of dilute sulfuric acid (H2SO4) solution.
- Observe the formation of a white precipitate if calcium ions are present.
- The equation for this reaction is: Ca^2+(aq) + H2SO4(aq) → CaSO4(s) + 2H+(aq)
5. If the test above is negative, it suggests that the solution may contain silver ions (Ag+).
6. Test for silver ions (Ag+):
- Add a few drops of the solution to a test tube.
- Add a small amount of dilute hydrochloric acid (HCl) solution.
- Observe the formation of a white precipitate if silver ions are present.
- The equation for this reaction is: Ag+(aq) + Cl^-(aq) → AgCl(s)
By following these steps and observing the precipitates formed, you can determine which solution is present in the unlabeled bottle.