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8/6/2019 Qualitative Conundrum
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Qualitative Conundrum
By: Raphael Jourdain L. Lim
8/6/2019 Qualitative Conundrum
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Group I Cations
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Lead (Pb)
� What we did?
± Added 2 drops of 1
Molar Potassium
Chromate ± This yielded Lead
Chromate
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Group II Cations
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Copper (Cu)
� What we did?
± Made the solution
acidic using HOAc and
added a drop of Potassium Ferro
cyanide
± We formed Copper
Ferro cyanide
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Cadmium (Cd)
� What we did
± Added 5%
thioacetamide to
solution and heated ± This formed a
Cadmium Sulfide
precipitate
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Group III Cations
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Nickel (Ni)
� What we did
± Added 1 drop of DMG
(Dimethylgloxime) to
solution ± This formed Nickel
Dimethygloxime
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Cobalt (Co)
� What we did
± Acidified solution with I
M HCl and added
Sodium Thiocyanatecrystals and acetone.
± This formed a blue
colored cobalt
complex.
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Manganese (Mn)
� What we did
± Added Sodium
Bismuthate and 2
drops of 4M Nitric Acid ± This produced purple
permanganate
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Iron III (Fe)
� What we did
± Added 2 drops of 0.2
M Potassium
Ferrocyanide ± This produced a blue
Ferric Cyanide
precipitate
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Aluminum (Al)
� What we did
± Added 2 drops
aluminon and 1 M
Ammonium Carbonateuntil basic
± This produced
Aluminum Hydroxide
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Chromate (Cr)
� What we did
± Added 1M HOAc until
acidic and 2 drops of
lead acetate
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Zinc (Zn)
� What we did
± Added 10 drops HCl
and 5 drops 0.1 M
PotassiumFerrocyanide
± This produced
Potassium-zinc-
hexacyanoferrate
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Group IV Cations
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Barium (Ba)
� What we did
± Added 1 drop 6M
Sulfuric Acid
± This produced a whiteprecipitate in the form
of Barium Sulfate
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Calcium (Ca)
� What we did
± Added 2 drops of
Ammonium Oxalate to
boiling solution ± This formed white
precipitate in Calcium
Oxalate
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Group V Cations
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Magnesium (Mg)
� What we did
± Added 2 drops of 1M
HOAc, 3 drops of
water, a drop of titanyellow and enough 6M
Sodium Hydroxide to
the white precipitate to
make it basic.
± The yellow precipitate
formed after
centrifugation is MgOH
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Anion Tests
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Thiocyanate (CNS)
� What we did
± Added a drop of Ferric
Nitrate to the test
solution ± The blood red colored
solution contains
Ferric Thiocyanate
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Iodine (I)
� What we did
± Added Nitric Acid and
2 drops of Ferric
Nitrate along withChloroform to the
solution
± This causes a purple
layer of iodine to form
on top of the solution
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Bromine (Br)
� What we did
± Added concentrated
Nitric Acid to Iodine
solution, boiled thencooled it before adding
chloroform
± The brownish layer on
top contains bromine
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Chlorine (Cl)
� What we did
± Acidified with nitric
acid, added a few
drops of water and 2drops of Silver Nitrate
to Bromine Solution
± The white precipitate
indicates Silver
Chloride is present
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Sulfide (S)
� What we did
± Placed a pinch of
sample in a beaker
and put watch glasswith a lead acetate
moistened filter paper
on top, warmed it and
observed
± The paper turns black
or silvery black
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Carbonate (CO3)
� What we did ± Prepared medicine
dropper with drop of Barium Hydroxide atthe tip and placed itinside test tube withsample though nottouching liquid thenwarmed the test tube.
± The drop turnedcloudy indicatingCarbonate
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Sulfate (SO4)
� What we did
± Acidified solution with
6M HCl and added a
drop of BariumChloride
± White precipitate
indicated Barium
Sulfate
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Chromate (CrO4)
� What we did
± Acidified solution with Nitric Acid and added
Hydrogen Peroxide
± The solution should turn blue indicating
chromate
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Phosphate (PO4)
� What we did
± Added 5 drops of concentrated nitric acid and
3 drops of ammonium molybdate
± Yellowish precipitate indicates phosphate
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Oxalate (C2O4)
� What we did
± Added 6M Acetic Acid and 2 drops of Calcium
Chloride, centrifuged and added water, 2
drops of both Sulfuric Acid and Permanganate
± If the color of permanganate fades within 30
seconds, oxalate is present.
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Acetate (CH3COO)
� What we did
± Added 2 drops of 1:1 conc. Sulfuric acid and
water.
± Presence of Vinegary odor indicates acetate
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Nitrate (NO3)
� What we did
± Added 10 drops
sulfuric acid and a
grain of FerrousSulfate.
± Presence of a brown
ring indicates nitrate is
present
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Thiosulfate (S2O3)
� What we did
± Added 3 drops of HCl
to solution.
± Cloudy, whitishprecipitate indicates
presence of thiosulfate
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Nitrite (NO2)
� What we did
± Acidified solution with 6 M HOAc and added 5
drops Potassium Ferricyanide and a drop of
Ferric Chloride.
± Deep red precipitate indicates Nitrite is
present