Which anion is confirmed with cl2

It is precipitated from a solution of the ammonia complex. Small traces of cations that form dark colored sulfides will obviously interfere. Aluminum is generally identified by making use of the amphoteric property of its hydroxide and the red color of the "lake" AlOH 3 forms with the reagent, aluminon. Aluminon is a dye an organic molecule, usually fairly large, that absorbs visible light. The adsorption of the dye is called "laking. Since most laboratory manipulations are carried out in glass containers, silica gel, which physically resembles aluminum hydroxide, is also a common impurity.

Centrifuge the mixture. Remove the mother liquor with a capillary pipet and wash the precipitate with distilled water. Centrifuge the mixture and remove the mother liquor with a capillary pipet.

These repeated washings remove other ions from the precipitate. Dissolve the precipitate in 3 M HNO 3. If any precipitate does not dissolve in the nitric acid, remove the supernatant to a clean test tube and discard the residue. Add two drops of aluminon reagent avoid any excess. Add 3 M NH 3 aq until the solution is basic. Silica gel is present in many solutions; it is leached from glass containers. Any silica gel present must be removed before the addition of the aluminon and the ammonia because silica gel will also give a red lake.

Do not confuse traces of red-brown ferric hydroxide for the red lake. Other precipitates will also form colors with the reagent. The supernatant liquid will be an intense blue-purple color if too much reagent has been added. This color has nothing to do with the presence of aluminum. The color of the reagent is sensitive to changes in pH, the reagent is an acid-base indicator. Chromium can be taken through a series of colored tests which leaves no doubt as to its identity.

Chromium III forms a steel green hydroxide which dissolves in excess strong base to give a deeply green colored solution of the hydroxy complex. The actual composition of this peroxide is not known, but it is believed to have the empirical formula CrO 5.

This peroxide readily decomposes to the pale violet color of the original hydrated chromium III ion. In low concentrations of dichromate the blue color is fleeting, and attention must be focused on the test tube during the addition of the hydrogen peroxide to avoid missing the color change.

Heat the test tube in the water bath until the excess H 2 O 2 is destroyed as indicated by the cessation of bubbles. Acidify the yellow solution with 3 M HNO 3. Cool the resulting orange solution in an ice bath. Place an iron brad or small iron wire in this solution and heat in a water bath for 5 minutes. Take the clear solution filter if necessary and add HgCl 2 solution dropwise. The appearance of a silky, white precipitate, which then turns black, confirms the presence of tin.

Heat must be avoided to prevent the decomposition of permanganate ion to brown, insoluble manganese dioxide. Chloride ion must be absent, because it reduces permanganate ion to either manganese dioxide or manganese II depending upon the conditions.

Acidify the test solution with 3 M HNO 3. Add solid NaBiO 3 and stir. Bismuth III forms a highly insoluble hydroxide which upon treatment with the hydroxy complex of tin II is immediately converted to free bismuth, a black precipitate. Then, to a solution of tin II chloride add with stirring 6 M sodium hydroxide until the precipitate of tin II hydroxide which first forms just redissolves.

This solution is then added dropwise to the precipitate of bismuth III hydroxide. The rapid formation of a black color confirms bismuth. A large excess of reagent should be avoided. Acidify the solution with 3 M HNO 3. The most characteristic reaction of carbonate is the formation of carbon dioxide upon treatment with acid:. The colorless, odorless carbon dioxide can be identified by bubbling it through a saturated solution of barium hydroxide, with which it forms a white precipitate of barium carbonate.

Assemble a gas-liberation apparatus from a small test tube and a section of bent tubing. Dissolve or suspend a portion of your compound in a small amount of water and place it in the small test tube. Add about 0. The formation of a white precipitate in the large test tube if the gas liberated is odorless is a positive test for carbonate. If the sulfide is very insoluble liberation of the gas may require concentrated acids indeed some sulfides, HgS, CuS, are so insoluble that dissolution requires special treatment.

The gas is generally identified by its odor and its precipitation of colored sulfides of various metal ions. Sulfides or hydrogen sulfide also are oxidized to elemental sulfur and sulfate by oxidizing agents such as permanganate, nitric acid, sulfuric acid, Fe III , etc.

Acidify a sample with 6 M hydrochloric acid and warm. Cautiously smell the gas evolved and also test the gas with a piece of filter paper moistened with lead acetate solution. A foul smelling gas which turns lead acetate paper black constitutes a positive sulfide test. Sulfate is conveniently identified by precipitation of BaSO 4.

Precipitation of these anions is prevented by acidifying the solution. Acidify the test solution with 6 M HCl, and add a few drops of 0. A white precipitate indicates the presence of SO 4 The most notable feature of the chemistry of the nitrate ion is its oxidizing ability as illustrated by the following reactions:.

It is the formation of this brown complex that is used to identify NO 3 - called the brown ring test. Cool the solution and then carefully introduce about 0. Allow the solution to sit undisturbed so that the sulfuric acid forms a definite layer. The formation of a brown color at the interface of the layer constitutes a positive test for nitrate. The precipitation usually used to identify phosphate is the formation of yellow ammonium molybdophosphate from ammonium molybdate in acidic solution.

Acidify the sample with concentrated nitric acid and add several drops in excess. Then treat the solution with ammonium molybdate reagent and warm. The formation of a yellow crystalline precipitate confirms the presence of phosphate.

All three of these anions form insoluble silver salts. Although the precipitates are of different colors AgCl white, AgBr cream, AgI yellow the colors are difficult to distinguish, and confirmatory tests are necessary. Silver chloride, the most soluble of the three, dissolves readily in 6 M NH 3 solution because of formation of the ammonia complex. Furthermore, when the solution of the ammonia complex is acidified, AgCl reprecipitates.

Note: To prepare magnesia mixture, add solid NH 4 Cl to magnesium chloride solution. Boil, cool and add NH 4 OH till a strong smell of ammonia ia obtained. Cite this Simulator:. Qualitative Analysis of Anions. Our Objective Our objective is to determine the anion present in the given salt.

Let's discuss the Qualitative Analysis of Anions. Qualitative Analysis of Anions Preliminary Tests Some preliminary tests are done before going to the anion analysis. A Physical Examination: Colour and Smell The physical examination of the unknown salt involves the study of colour, smell and density. B Dry Heating Test This test is performed by heating a small amount of salt in a dry test tube. C Identification of Anions Acid Radicals The identification of the radicals is first done on the basis of the preliminary tests.

H 2 SO 4 but not with dil. H 2 SO 4 to produce characteristic gases. These are, therefore, identified by individual tests. Thus, these anions may be identified by performing the following tests below: 1 Dil. H 2 SO 4 Tests Treat a pinch of the salt with dil. Chemical Reactions Involved in Dil. H 2 SO 4 Test If no action takes place with dil. Chemical Reactions Involved in Conc. Confirmation of Sulphite SO 3 2- a Barium chloride test Sulphites on reaction with barium chloride to form a white precipitate of barium sulphite.

Confirmation of Nitrate NO 3 - a Diphenylamine test In the presence of nitrates, diphenylamine is oxidised, giving a blue colouration. Confirmation of Chloride Cl - a Silver nitrate test Chlorides on reaction with silver nitrate solution to form a white precipitate of silver chloride which is soluble in ammonium hydroxide. Confirmation of Bromide Br - a Silver nitrate test Bromides on reaction with silver nitrate solution forms a pale yellow precipitate of silver bromide which is sparingly soluble in ammonium hydroxide.

Confirmation of Iodide I - a Silver nitrate test Iodides on reaction with silver nitrate solution forms an yellow precipitate of silver iodide which is insoluble in ammonium hydroxide. Confirmation of Acetate CH 3 COO - a Oxalic acid test Oxalic acid reacts with acetate salt to form acetic acid which has a characteristic vinegar like smell. Confirmation of Oxalate C 2 O 4 2- a Calcium chloride test Oxalate salts react with calcium chloride to form white precipitate of calcium oxalate.

Confirmation of Sulphate SO 4 2- a Barium chloride test Sulphates react with barium chloride to form white precipitate of barium sulphate. Confirmation of Phosphate PO 4 3- a Ammonium molybdate test Phosphate salts react with ammonium molybdate solution to form a deep yellow precipitate of ammonium phosphate molybdate. The chemical reaction is as follows: b Magnesia mixture test Phosphate salts react with magnesia mixture to form white precipitate of magnesium ammonium phosphate.

Learning Outcomes: Students understand different types of anions. Students understand various tests to identify the anion present in a given salt. Students understand the chemical reactions and their balanced equations that takes place during each test. Students acquire the skill to perform the experiment in the real lab once they understand different steps in the procedure. Move containers from the fire area if it is possible to do so without risk to personnel.

Damaged cylinders should be handled only by specialists. For fire involving tanks, fight the fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after the fire is out. Do not direct water at the source of the leak or at safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tanks.

Always stay away from tanks engulfed in fire. For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from the area and let the fire burn.

Run-off from fire control may cause pollution. If the situation allows, control and properly dispose of run-off effluent. Small spills involving the release of approximately Then protect persons downwind during the day: 0. Then protect persons downwind during the night: 0. Large spills involving quantities greater than Then protect persons downwind during the day: 1.

Then protect persons downwind during the night: 4. They will spread along the ground and collect and stay in poorly-ventilated, low-lying, or confined areas e. Hazardous concentrations may develop quickly in enclosed, poorly-ventilated, or low-lying areas. Keep out of these areas. Stay upwind.

Symptoms generally resolve within 6 hours after mild exposures, but may continue for several days after severe exposures. Deterioration may continue for several hours. At low concentrations, chlorine can cause eye and nose irritation, sore throat, and cough.

At high exposure levels, irritation of the upper respiratory tract and accumulation of fluid in the lungs pulmonary edema contribute to a sensation of choking. The majority of deaths occur within 24 hours and are due to respiratory failure. Severe: Corneal burns leading to cell death necrosis and tissue damage ulceration.

Severe: Severe chemical burns leading to cell death necrosis and tissue damage ulceration. Care should be taken during decontamination, because absorbed agent can be released from clothing and skin as a gas. Your Incident Commander will provide you with decontaminants specific for the agent released or the agent believed to have been released. The warm zone should include two decontamination corridors.

One decontamination corridor is used to enter the warm zone and the other for exiting the warm zone into the cold zone. The decontamination zone for exiting should be upwind and uphill from the zone used to enter. Decontamination area workers should wear appropriate PPE. See the PPE section of this card for detailed information. A solution of detergent and water which should have a pH value of at least 8 but should not exceed a pH value of Soft brushes should be available to remove contamination from the PPE.

Labeled, durable 6-mil polyethylene bags should be available for disposal of contaminated PPE. Always move in a downward motion from head to toe. Make sure to get into all areas, especially folds in the clothing. Wash and rinse using cold or warm water until the contaminant is thoroughly removed. Place all PPE in labeled durable 6-mil polyethylene bags. Remove all clothing at least down to their undergarments and place the clothing in a labeled durable 6-mil polyethylene bag.

First Aid. There is no post-exposure therapy specifically for chlorine inhalation. Immediately decontaminate eyes with large amounts of tepid water for at least 15 minutes. Seek medical attention immediately. Evaluate respiratory function and pulse. If shortness of breath occurs or breathing is difficult dyspnea , administer oxygen. Assist ventilation as required. Always use a barrier or bag-valve-mask device.

If breathing has ceased apnea , provide artificial respiration.