Groups of Cations

Question 1

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.

Answer 1

Cd²⁺

Question 1

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

Answer 1

Ba²⁺

Question 2

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 H2​S which does not dissolve in excess (NH₄)₂CO_3.

Answer 2

Sn⁴⁺

Question 2

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

Answer 2

Al³⁺

Question 3

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

Answer 3

Sn²⁺

Question 3

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 H₂​S which dissolves in excess (NH4)₂CO3.

Fresh sample + 1:1 HCl + KI yields no coloration.

Answer 3

As³⁺

Question 5

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.

Answer 5

Cu²⁺

Question 6

Cation which forms a precipitate with dilute HCl. Upon addition of NH₃no change will be observed

Answer 6

Lead

Question 7

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

Answer 7

Sr²⁺

Question 8

Cation which forms a precipitate with dilute HCl and turns **BLACK **upon the addition of NH₃

Answer 8

Hg₂²⁺

Question 8

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

Answer 8

Co²⁺

Question 9

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.

Answer 9

Ni²⁺

Question 10

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

Answer 10

Cr³⁺

Question 11

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.

Answer 11

Mn²⁺

Question 13

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 H₂​S. Fresh sample + 1:1 HCl + KI yields Brown Color

Answer 13

Sb⁵⁺

Question 14

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

Answer 14

Na⁺

Question 15

Cation which forms a precipitate with dilute HCl and dissolves upon the addition of NH₃

Answer 15

Ag⁺

Question 17

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 H2​S which **DISSOLVES **in excess (NH4)2CO3.

Fresh sample + 1:1 HCl + KI yields **BROWN **coloration.

Answer 17

As4⁺

Question 19

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 H₂​S. Fresh sample + 1:1 HCl + KI yields no color.

Answer 19

Sb³⁺

Question 20

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

Answer 20

Fe²⁺

Question 21

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.

Answer 21

Hg²⁺

Question 22

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

Answer 22

Fe³⁺

Question 23

Cation that does not react with HCl, H₂S in dilute mineral acid medium, (NH₄)₂S and NH₄Cl.

Forms a** WHITE **precipitate with SODIUM BITARTRATE

Answer 23

K+

Question 24

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

Answer 24

Ca²⁺

Question 25

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

Answer 25

NH₃

Question 26

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

Answer 26

Zn²⁺

Question 27

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.

Answer 27

Bi³⁺

Question 28

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.

Answer 28

Mg²⁺