Anions and Cations practical !

[silva]

If your not sure about this test.. it involves silver nitrate and ammonia? o.O actually lemme just type what the instructions of the experiment is..:

 

1. place about 5ml of unknown solution into a labelled boiling tube

2. add one drop of nitric acid to the tube with the unknown solution

3. add one or two drops of silver nitrate to the tube with the solution and silver nitrate

4. record the change you see in the table below

5. add three drops of ammonia solution to the tube with the halide solution and silver nitrate

6. record what you see in the table below

7. repeat using a clean test tube until you have results for all of the unknown solutions

8. only one anion should be present: if any of the unknown solutions did not give a visible result, move on to the next test

 

OK. that was long :/

so the question is: In the first test for anions (which is what I just typed ^ ), what was formed to make a colour change, and why did a second occur when ammonia was added?

 

There's only 4 lines for me to write in.. and I wrote: Because the silver nitrate is soluble it precipitated out creating cloudy liquid and when the ammonia was added it dissolved, making it clear again.

 

The teacher wrote back: Silver nitrate is soluble so did not precipitate. A silver compound did precipitate, what was this?

 

PPPLLLLEEEAAASSSEEEE HELP MEEEE!!! I only have 4 MORE DAYS TILL THE END OF COLLEGE! I got so much to do and this one assignment is BUGGING me caz I don't get it! :/

 

THANK YOU SOOO MUCH if you reply!

[Bioc]

Hi, since I infer you precipitated silver with an halide, here is a link where you can get some info:

 

http://employees.oneonta.edu/kotzjc/LAB/SilverGroup.pdf

 

The question is not that hard, don't give up!