Groups of Cations Flashcards
Cation that does not react with HCl, forms a PRECIPITATE in H2S in dilute mineral acid medium, and forms a YELLOW precipitate with Ammonium Polysulfide.
Cd2+
Cation that does not react with HCl, H2S in dilute mineral acid medium and (NH4)2Sbut forms a **WHITE **precipitate with NH4Cl.
Fresh Sample + Saturated CaSO4 yields a **WHITE **precipitate immediately
Ba2+
Cation that does not react with HCl, forms a PRECIPITATE in H2S in dilute mineral acid medium, SOLUBLE in Ammonium Polysulfide and a fresh sample forms a YELLOW precipitate with Acidified H2S which does not dissolve in excess (NH4)2CO3.
Sn4+
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a WHITE precipitate with (NH4)2S.
Fresh sample + NH3 forms a WHITE precipitate insoluble in excess reagent
Al3+
Cation that does not react with HCl, forms a PRECIPITATE in H2S in dilute mineral acid medium, SOLUBLE in Ammonium Polysulfide and a fresh sample forms a **BROWN **precipitate with Acidified H2S
Sn2+
Cation that does not react with HCl, forms a **PRECIPITATE **in H2S in dilute mineral acid medium, SOLUBLE in Ammonium Polysulfide and a fresh sample forms a YELLOW precipitate with Acidified H2S which dissolves in excess (NH4)2CO3.
Fresh sample + 1:1 HCl + KI yields no coloration.
As3+
Cation that does not react with HCl, forms a PRECIPITATE in H2S in dilute mineral acid medium, INSOLUBLE in Ammonium Polysulfide and a fresh sample forms a **BLUE **precipitate with NaOH.
Cu2+
Cation which forms a precipitate with dilute HCl. Upon addition of NH3no change will be observed
Lead
Cation that does not react with HCl, H2S in dilute mineral acid medium and (NH4)2S but forms a WHITE precipitate with NH4Cl.
Fresh Sample + Saturated CaSO4 yields a **WHITE **precipitate slowly
Sr2+
Cation which forms a precipitate with dilute HCl and turns **BLACK **upon the addition of NH3
Hg22+
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a** BLACK** precipitate with (NH4)2S which is INSOLUBLE in 1:1 HCl
Fresh sample + NaOH yields a BLUE precipitate which turns PINK upon standing
Co2+
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a BLACK precipitate with (NH4)2S which is INSOLUBLE in 1:1 HCl
Fresh sample + NaOH yields a GREEN precipitate.
Ni2+
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a **GREEN **precipitate with (NH4)2S.
Fresh sample + NaOH forms a **GREEN **precipitate soluble in excess reagent
Cr3+
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a PINK precipitate with (NH4)2S.
Fresh sample + NaOH forms a WHITE precipitate that turns **DARK **upon standing.
Mn2+
Cation that does not react with HCl, forms a **PRECIPITATE **in H2S in dilute mineral acid medium, SOLUBLE in Ammonium Polysulfide and a fresh sample forms an ORANGE precipitate with Acidified H2S. Fresh sample + 1:1 HCl + KI yields Brown Color
Sb5+
Cation that does not react with HCl, H2S in dilute mineral acid medium, (NH4)2S and NH4Cl.
Forms a **YELLOW **precipitate with COBALT URANYL ACETATE
Na+
Cation which forms a precipitate with dilute HCl and dissolves upon the addition of NH3
Ag+
Cation that does not react with HCl, forms a PRECIPITATE in H2S in dilute mineral acid medium, **SOLUBLE **in Ammonium Polysulfide and a fresh sample forms a YELLOW precipitate with Acidified H2S which **DISSOLVES **in excess (NH4)2CO3.
Fresh sample + 1:1 HCl + KI yields **BROWN **coloration.
As4+
Cation that does not react with HCl, forms a PRECIPITATE in H2S in dilute mineral acid medium, SOLUBLE in Ammonium Polysulfide and a fresh sample forms an ORANGE precipitate with Acidified H2S. Fresh sample + 1:1 HCl + KI yields no color.
Sb3+
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a BLACK precipitate with (NH4)2S which is soluble in 1:1 HCl
Fresh sample + NaOH yields a **GREEN **precipitate which turns **DARK **upon standing
Fe2+
Cation that does not react with HCl, forms a **PRECIPITATE **in H2S in dilute mineral acid medium, INSOLUBLE in Ammonium Polysulfide and a fresh sample forms a YELLOW precipitate with NaOH.
Hg2+
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a **BLACK **precipitate with (NH4)2S which is soluble in 1:1 HCl
Fresh sample + NaOH yields a REDDISH BROWN
Fe3+
Cation that does not react with HCl, H2S in dilute mineral acid medium, (NH4)2S and NH4Cl.
Forms a** WHITE **precipitate with SODIUM BITARTRATE
K+
Cation that does not react with HCl, H2S in dilute mineral acid medium and (NH4)2Sbut forms a WHITE precipitate with NH4Cl.
Fresh Sample + Saturated CaSO4 yields no precipitate
Ca2+
Cation that does not react with HCl, H2S in dilute mineral acid medium, (NH4)2S and NH4Cl.
Vapors turn red litmus to blue when heated with NaOH
NH3
Cation that does not react with HCl and H2S in dilute mineral acid medium but forms a **WHITE **precipitate with (NH4)2S.
Fresh sample + NH3 forms a WHITE precipitate soluble in excess reagent
Zn2+
Cation that does not react with HCl, forms a PRECIPITATE in H2S in dilute mineral acid medium, INSOLUBLE in Ammonium Polysulfide and a fresh sample forms a WHITE precipitate with NaOH.
Bi3+
Cation that does not react with HCl, H2S in dilute mineral acid medium, (NH4)2S and NH4Cl.
Forms a WHITE precipitate with excess NaOH which turns RED upon the addition of TITAN YELLOW reagent.
Mg2+
