Coloured Complex Ions (cognito)

Question 1

Iron (II) aqueous ion

Answer 1

[Fe(H2O)6]2+ (aq)

Green solution

Question 2

Iron (II) + NaOH (aq)

Answer 2

Fe(OH)2(H2O)4 (s)

Green PPT
Brown in air

Question 3

Iron (II) + excess NaOH (aq)

Answer 3

Nothing

Question 4

Iron (II) + NH3 (aq)

Answer 4

Fe(OH)2(H2O)4 (s)

Green PPT
Brown in air

Question 5

Iron (II) + excess NH3 (aq)

Answer 5

Nothing

Question 6

Copper (II) aqueous ion

Answer 6

[Cu(H2O)6]2+ (aq)

Blue solution

Question 7

Copper (II) + NaOH (aq)

Answer 7

Cu(OH)2(H2O)4 (s)

Blue PPT

Question 8

Copper (II) + excess NaOH (aq)

Answer 8

Nothing

Question 9

Copper (II) + NH3 (aq)

Answer 9

Cu(OH)2(H2O)4 (s)

Blue PPT

Question 10

Copper (II) + excess NH3 (aq)

Answer 10

[Cu(NH3)4(H2O)2]2+ (aq)

Dark blue solution

Question 11

Manganese (II) aqueous ion

Answer 11

[Mn(H2O)6]2+ (aq)

Pink solution

Question 12

Manganese (II) + NaOH (aq)

Answer 12

Mn(OH)2(H2O)4 (s)

Light brown PPT
Dark brown in air

Question 13

Manganese (II) + excess NaOH (aq)

Answer 13

Nothing

Question 14

Manganese + NH3 (aq)

Answer 14

Mn(OH)2(H2O)4 (s)

Light brown PPT
Dark brown in air

Question 15

Manganese (II) + excess NH3 (aq)

Answer 15

Nothing

Question 16

Iron (III) aqueous ion

Answer 16

[Fe(H2O)6]3+ (aq)

Yellow solution

Question 17

Iron (III) + NaOH (aq)

Answer 17

Fe(OH)3(H2O)3 (s)

Brown PPT

Question 18

Iron (III) + excess NaOH

Answer 18

Nothing

Question 19

Iron (III) + NH3 (aq)

Answer 19

Fe(OH)3(H2O)3 (s)

Brown PPT

Question 20

Iron (III) + excess NH3 (aq)

Answer 20

Nothing

Question 21

Chromium (III) aqueous ion

Answer 21

[Cr(H2O)6]3+ (aq)

Violet solution

Question 22

Chromium (III) + NaOH (aq)

Answer 22

Cr(OH)3(H2O)3 (s)

Gray-green PPT

Question 23

Chromium (III) + excess NaOH (aq)

Answer 23

[Cr(OH)6]3- (aq)

Dark green solution

Question 24

Chromium (III) + NH3 (aq)

Answer 24

Cr(OH)3(H2O)3 (s)

Gray-green PPT

Question 25

Chromium (III) + excess NH3 (aq)

Answer 25

[Cr(NH3)6]3+ (aq) Purple solution