Anachem-Lab-M6 Activity 2-LAB PDF

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ANALYSIS OF ANIONSA. Identification of Anions: (from the Videos Qualitative Analysis of anions) Anion ConfirmatoryReagentPositive Result Chemical Formula ofPositive ResultCarbonate (Video1) dilute Nitric Acid White precipitate that will dissolve upon further bubblingCO 2 (g)Chloride (Video1) dilute ...

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ANALYSIS OF ANIONS

Anion

A. Identification of Anions: (from the Videos Qualitative Analysis of anions) Confirmatory Positive Result Chemical Formula of Reagent Positive Result

Carbonate (Video1)

dilute Nitric Acid

White precipitate that will dissolve upon further bubbling

CO2 (g)

Chloride (Video1)

dilute Nitric Acid followed by Silver Nitrate solution

White precipitate that will dissolve upon addition of aqueous ammonia

AgCl(s)

Iodide (Video1)

dilute Nitric Acid followed by lead (II) nitrate solution

yellow precipitate

PbI2(s)

Sulfate (Video 1)

dilute Nitric Acid followed by Barium nitrate solution.

white precipitate

BaSO4(s)

Chloride (Video 2)

silver nitrate solution

white precipitate

AgCl(s)

Bromide (Video 2)

silver nitrate solution

pale cream precipitate

AgBr(s)

Iodide (Video 2)

silver nitrate solution

pale yellow precipitate

AgI(s)

Carbonate (Video 2)

dilute hydrochloric acid or dilute nitric acid

colorless gas that will turn milky if allowed to pass into lime water.

reaction with acid: CO2 (g)+ 3H2O(l) reaction with lime water: CaCO3 (s) + H2O (l)

Hypochlorite (Video 2)

Stain a piece of litmus paper with a solution of hypochlorite ion

litmus paper turns blue, and is then bleached to white

Sulfite (Video 2)

-acidified potassium dichromate solution

- turns from orange to green

None

3SO42-(aq) + 2Cr3+(aq) + 4H2O(l)

-acidified potassium permanganate

-purple to colorless

5SO42-(aq) + 2Mn2+(aq)+ 3H2O(l) -bromine water

-brown bromine water to colorless

SO42-(aq) + 2Br-(aq)+ 2H+(aq) B. Guide questions: (From the discussion of the ppt on Analysis of Anions) 1. What type of reaction is involved in the following: a. CaC2O4 + KMnO4 (in the presence of H2SO4) Redox Reaction b. AsO4-3 + KI ( in the presence of CHCl 3) Redox Reaction c. SO4-2 + Ba(C2H3O2)2 (in the presence of HCl) Precipitation Reaction d. AgSCN + FeCl3 Redox Reaction 2. In the identification of iodide ion, the following redox reaction occurs. 2AgI + Zn → 2Ag + 2I- + Zn+2 a. AgI acts as a/an Oxidizing Agent b. Zn acts as a/an Reducing Agent 3. In the identification of chlorate ion, this half reaction occurs ClO3→ Cla. This half reaction is called a/an Reduction b. What is the change in the oxidation number of chlorine? +6 to -1 c. Does the reaction involve loss or gain of electrons? Gain of electrons C. After studying and answering the questions in the Schematic Diagram for the Separation of Anions , write your answers here for the 10 questions given in the diagram. 1. +Ca(Ac) 2. +Ba(Ac)2 3. +Cd(Ac)2 4. +Ag(Ac), +HNO2 5. Group 1 Anion (AsO4-3 , SO3-2 , C2O4-2) 6. Group 2 Anion (SO4-2 , CrO4-2) 7. Group 3 Anion (S-2 , Fe(CN)6-4)

8. Group 4 Anion (CNS- , I-) 9. ClO310. BO3-3...