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Clean beakers and test tubes (make sure small test tubes).
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Grab strips of different colored washi tape for labeling.
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Grab disposable pipettes.
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Fill soap and distilled water.
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Separation of Qual II ions done with strong base, NaOH.
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Mn 2+, Ni2+, Fe2+. Will precipitate as a Hydroxides.
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Al3+ and Zn2+ will precipitate soluble Hydroxides.
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Add 2 mL of original solution to small cleaned test tube. (DO NOT USE 2 mL WHEN DOING UNKNOWN)
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Add 15 drop of 6M NaOH
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Centrifuge and save precipitate and supernate. (Test for incomplete reaction; several drops of 6 M NaOH)
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Label supernate "Al & Zn ions".
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Dissolve the precipitate with the minimum amount of concentrated Nitric Acid (HNO3) possible.
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If necessary heat the solution.
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Label dissolved, " Mn, Ni, & Fe ions"
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Add approximatly 1/2 of "Mn, Ni, & Fe" to a small test tube. (DO NOT USE THAT MUCH IF DOING QUAL II UNKNOWN."
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Add solid NaBiO3 in excess to the solution and centrifuge.
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Deep purple solution confirms Mn 2+ ion presence.
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Add remaining 1/2 solution of "Mn, Ni, & Fe" (DO NOT USE ALL IF DOING QUAL II UNKNOWN"
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Excess ammonia does not react with Mn the addition is to make Fe a brown precipitate and Ni a blue supernate.
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Add 5 drops of $M NH4Cl to the solution
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Add concentrated ammonium hydroxide (NH4OH) till it is basic to litmus.
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Add additional three drops to check for reaction completion.
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Centerfuge & save supernate label for Ni testing
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Dissolve percipitate with 6M HCl
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Add 5 drops of 0.1M NH4SCN. Presence of blood red color confirms presence of Fe.
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Complexing agent (Dimethylglyoxime) reacting specifically with Ni ions
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Using test tube labeled Ni supernate
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Appearance of pinkish red precipitate.
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Addition of acid breaks down Al & Zn Hydroxides to ions
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Add HNO3 drop wise to supernated labeled "Zn & Al ions" solution must be basic to litmus paper.
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Add 5 more drops after that to insure reaction completion.
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Presence of white cloudy percipitate indicated presence of Al ions.`
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Centerfuge and save Zn supernate for analysis.
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Addition of 6M HCl to supernate Zn+ until solution is acidic to litmus paper
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Add 3 drop of 0.2M K4[Fe(CN)6] and stir.
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Centrifuge and discard supernate.
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Light green precipitate confirms presence of Zn.
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