Take four test tubes from the Containers shelf and place them on the workbench.
Fill each test tube with a different halide solution from the Materials shelf, as directed below. You may want to label the test tubes by double-clicking on each test tube and renaming it.
Test Tube # Halide Solution
1 10.5 mL 0.1 M sodium chloride
2 10.5 mL 0.1 M sodium fluoride
3 10.5 mL 0.1 M sodium iodide
4 10.5 mL 0.2 M potassium bromide
Take 0.5 M calcium nitrate from the Materials shelf and add 4.5 mL to each of the four test tubes. You may want to use the + or â zoom buttons in the lower right of the screen for a closer view. Record any evidence of a reaction with each of the four halide ions in your Lab Notes. Remember to press Save Notes.
Dispose of the four test tubes by dragging them to the recycling bin beneath Experiment 1: Observe the Reactions Between Halide and Calcium Ions
the workbench.
Experiment 2: Observe the Reactions Between Halide and Silver Ions
Prepare another set of four test tubes with the halogen ions as described in steps 1 and 2 of experiment 1.
Take 0.1 M silver nitrate from the Materials shelf and add 4.5 mL to each of the four test tubes. Observe and record any evidence of a reaction with each of the four halide ions in your Lab Notes. You may want to zoom in for a closer look.
Dispose of the four test tubes by placing them in the recycling bin.
Experiment 3: Observe the Reactions Between Silver Halides and Ammonia
Take four 50 mL beakers from the Containers shelf and place them on the workbench.
Fill each beaker with a different halide solution from the Materials shelf, as directed below. You may want to label the beakers by double-clicking on each one and renaming it.
Beaker # Halide Solution
1 10.5 mL 0.1 M sodium chloride
2 10.5 mL 0.1 M sodium fluoride
3 10.5 mL 0.1 M sodium iodide
4 10.5 mL 0.2 M potassium bromide
Take 0.1 M silver nitrate from the Materials shelf and add 4.5 mL to each beaker. Observe and record any evidence of a reaction with each of the four halogen ions in your Lab Notes.
Take 4 M ammonia from the Materials shelf and add 4.5 mL to each beaker. Observe and record any evidence of a reaction with each of the four halogen ions in your Lab Notes.
Dispose of the four beakers by placing them in the recycling bin.
Experiment 4: Observe the Reactions Between Silver Halides and Sodium Thiosulfate
Prepare another set of beakers with the halide ions as described in steps 1 and 2 of experiment 3.
Take 0.1 M silver nitrate from the Materials shelf and add 4.5 mL to each beaker. Observe and record any evidence of a reaction with each of the four halogen ions in your Lab Notes.
Take 0.2 M sodium thiosulfate from the Materials shelf and add 4.5 mL to each beaker. Observe and record any evidence of a reaction with each of the four halogen ions in your Lab Notes.
Dispose of the four beakers by placing them in the recycling bin.
Experiment 5: Identify Unknown Halides
On the Materials shelf, there are two unidentified halide solutions. Each solution contains one of the four halide ions from the previous four experiments. Identify them using the reagents and
Questions
1. Suppose you forgot to label your test tubes and you do not remember their order. Can you identify the sodium fluoride solution using only the reaction with silver nitrate?
a. Yes sodium floride will form a white precipitate with silver nitrate
b. No both sodium floride and potassium bromide will form a yello precipitate with silver
c. Yes sodium floride will not form a precipitate with silver nitrate
d. No sodium floride does not form a precipate with silver nitrate
2. How can you identify the sodium chloride containing test tube using only the reactions with silver nitrate?
a. Sodium chloride does not form a white pecipate with silver nitrate
b. Sodium chloride forms a pale yellow precipitate with silver nitrate
c. Sodium chloride forms a yellow precipate with silver
d. Sodium chloride forms a white precipate with silver nitrate
3. Which of the following statements are true?
a. Silver nitrate fomed precipates in the presence of floride,bromide and iodine ions
b. Silver nitrate formed precipates in the presence of chloride, bromide, and fluoride ions
c. Silver nitrate fomed precipates in the presence of chloride, floride, and iodine ions
d. Silver nitrate fomed precipitaes in the prensence of chloride,bromide and iodine ions
4. If you were allowed to react your unknown halides with only one of the reagents used in this lab, which reagent will you pick and why?
a. Ammonia because it forms colored precipitaes with both halides
b. Silver nitrate because it forms different color precipitates with the two halides
c. Calcium nitrate because it forms a precipate with only one of the halides
d. Sodium thiosulfate because it changes the color of the halide solutions
5. How would you expect the results to change if the identity of the cation were to change?
a. There would be increased solubility in the prensence of ammonia
b. There would be no change since these test are for the halide ion
c. The next change of the solution would increase
d. There would be increased precipation of the halide ion upon the addition of silver nitrate
