Procedure

1. Before get downing. put up a information tabular array similar to the Data Table: Qualitative Anion Trials in the Lab Report Assistant subdivision.
2. Each anion tested will necessitate the usage of three separate trial tubings. Complete all of the undermentioned trials on one solution. enter your observations. and so thoroughly clean and dry the trial tubing before get downing trials on the following solution.
3. After consecutively proving the identified anions. execute the same trials on the unknown solution to once and for all find its individuality.
4. First trial tubing:

a. Put 8 beads of the anion to be tested in a clean little trial tubing. B. Add 8 beads of hydrochloric acid to the anion solution. Note the visual aspect of the solution plus any development of gas and olfactory properties of gas.

5. Second trial tubing:

a. Put 8 beads of the anion solution in a 2nd trial tubing.
B. Add 3 beads of Ag nitrate solution.
c. Note the colourss of any precipitates formed.
d. Write a net ionic equation for any reaction that produces a precipitate. e. Acidify the trial tubing by adding a few beads of azotic acid. f. Mix well and note if the precipitate dissolves or remains. 6. Third trial tubing: Per the followers. execute the appropriate verification trial for this anion. Note: Where the undermentioned instructions call for “gently warming” a chemical topographic point the trial tubing incorporating the chemical into a 50-mL beaker of hot tap H2O for a few proceedingss.

? Bromide ( Br- ) and Iodide ( I- ) : ( First make fresh Cl H2O by uniting in a calibrated cylinder about 1ml of bleach. 5ml of tap H2O. and 6 beads of HCl ; splash or shingle. Then label an empty pipet and suck up this Cl solution for usage here. ) To 10 beads of the trial solution add 2 to 3 beads of the organic reagent ( hexanes or similar ) and several beads of chlorine H2O. Shake good and let the lower bed to settle out. Note the colour in the organic reagent bed. A brown or gold colour indicates Br and a reddish-violet or tap colour indicates I. Carbonate ( CO32- ) : Acidify 20 beads of the solution with 2 beads of HCl. Carbonates produce an odorless gas ( CO2 ) which should bring forth a precipitate when bubbled through a concentrated Ca hydroxide solution. For the intent of this experiment you may separate this gas from H sulphide by its deficiency of olfactory property ( See sulfide test. S2- ) .

? Chloride ( Cl- ) : To 6 beads of the trial solution add 2 beads of AgN03. Ag nitrate solution. A white precipitate that dissolves readily when the solution is made decidedly basic with aqueous ammonium indicates the presence of the chloride ion. ? Phosphate ( PO43- ) : Acidify 10 beads of the trial solution with 1 bead of HNO3. azotic acid. and add 7 beads of ammonium molybdate solution ( agitate it good before utilizing ) . Wait 30 seconds. The phosphate should bring forth a xanthous precipitate. Gentle heating may be necessary to obtain the precipitate. ? Sulfate ( SO4 2- ) : To 10 beads of the trial solution add 5 beads of the BaCl2. Ba chloride solution. A white precipitate that is indissoluble in HCl indicates the presence of sulphate.

? Sulfide ( S2- ) : Acidify 10 beads of the trial solution with HCl. The olfactory property of H sulphide ( H2S ) should be evident ( it smells like icky eggs! ) . Warm the solution reasonably and so keep a little piece of damp lead acetate paper at the oral cavity of the trial tubing. If the paper turns black ( caused by PbS ) this indicates the presence of sulphide. Thoroughly clean and dry the trial tubing before get downing trials on the following solution. Killing: Tightly cap the bottle of Ag nitrate solution and set it in the Experiment 11 bag so it will be easy to happen when you need it for the following experiment. Flush any other staying solutions down the drain with tonss of H2O. Properly rinse all equipment used. so dry and shop for future usage.

Data and Observation

Datas Table: Qualitative Anion Trials Name
Test tubing 1
w/HCI
Test tubing 2
w/AgNO3
w/HNO3
Test tubing 3
Confirmation
Bromide
Gas and no odor
Precipitate. didn’t dissolve
Didn’t dissolve
Iodine separated from Bromide
Carbonate
Gas and no odor
Cloudy Precipitate
Clear gas nowadays
Clear and no odor
Chloride
Gas and no odor.
No precipitate

Cloudy precipitate nowadays
Didn’t dissolve
Dissolve with hasty nowadays
Iodine
Gas and no odor
Precipitate. didn’t dissolve
Didn’t dissolve
Iodine separated from Bromide
Phosphate
Gas and no odor
Cloudy and xanthous precipitate nowadays
Dissolve
Yellow with hasty nowadays
Sulfate
Gas and no odor
Precipitate nowadays
Didn’t dissolve
White precipitate nowadays
Sulfide
Gas and clear
Precipitate nowadays
Didn’t dissolve
Had an olfactory property with hasty nowadays.
Turned Black
Unknown
No alteration
No alteration
White precipitate nowadays
Sulfate didn’t dissolve

Questions:
Group 1: Anions that WILL NOTPRECIPITATE in the presence of Ag nitrate.

Sulfate

Group 2: Anions that WILL PRECIPITATE in the presence of Ag nitrate and the ensuing precipitates WILL DISSOLVE upon acidification with azotic acid.

Carbonate. Phosphate

Group 3: Anions that WILL PRECIPITATE in the presence of Ag nitrate and the ensuing precipitates WILL NOT DISSOLVE upon acidification with azotic acid.

Bromide. Chloride. Iodide. Sulfide

A. Write a net ionic equation for any reaction that produces a precipitate.

Sodium Bromide:
Ag+ ( aq ) + Br- ( aq ) ( AgBr ( s )
Sodium Carbonate:
2Ag+ ( aq ) + CO32- ( aq ) ( Ag2CO3 ( s )
Sodium Chloride:
Ag+ ( aq ) + Cl- ( aq ) ( AgCl ( s )
Sodium Iodide:
Ag+ ( aq ) + I- ( aq ) ( AgI ( s )
Sodium Phosphate:
Ag+ ( aq ) + PO4- ( aq ) ( Ag3PO4 ( s )
Sodium Sulfide:
2Ag+ ( aq ) & A ; S-2 ( aq ) ( Ag2S ( s )

B. Identify the anions that produce gas upon add-on of HCl.

Carbonate. Sulfide

C. Identify the anions that do non precipitate with silver nitrate.

Sulfate

D. Identify the anions that react with Ag nitrate to organize precipitates that dissolve when acidified with azotic acid.

Carbonate. Phosphate
E. Identify the anions that react with Ag nitrate to organize precipitates that do non fade out when acidified with azotic acid.

Bromide. Chloride. Iodide. Sulfide

F. What simple trial ( other than a specific verification trial ) would separate between CO3 2-and NO- ?

Add Barium Chloride. If there is CO32- a white precipitate of BaCO3 will look.

Decisions:

Through this experiment. I learned how to place normally happening anions. I besides learned how to utilize the features of their reactions with HCl and AgNO3 to place an unknown solution. Using my observations with the different anion mixtures. I was able to place the Unknown anion to be Sodium Sulfate. I figured this out because when HCl was added. no gas was formed. This ruled out Sodium Carbonate and Sodium Sulfide. The gas I observed for the Sodium Carbonate & A ; Sulfide was really elusive. Even so I was non 100 % certain. This is where I think at that place could hold been room for mistake because I did non read the consequences right. therefore perchance interfering with my unknown. However. the unknown did non organize a precipitate and there was merely one other anion that did this.