Transition metal colours

Question 1

Cr³⁺ :

Metal aqua ion

With OH^-

With excess OH^-

Answer 1

Metal aqua ion = Violet Solution
[Cr(H₂O)6]3+

With OH− = Green Precipitate
Cr(OH)3(H₂O)3

With excess OH− = Green Solution
[Cr(OH)6]3-

Question 2

Fe²⁺

Metal aqua ion

With OH^-

With excess OH^-

Answer 2

Metal aqua ion = Green Solution
[Fe(H₂O)6]²⁺

With OH^- = Green Precipitate
Fe(OH)2(H₂O)4

With excess OH^- = no change

Question 3

Fe³⁺ :

Metal aqua ion

With OH^-

With excess OH^-

Answer 3

Metal aqua ion = Yellow Solution
[Fe(H₂O)6]3+

With OH− = Brown Precipitate
Fe(OH)3(H₂O)3

With excess OH− = no change

Question 4

Mn²⁺ :

Metal aqua ion

With OH^-

With excess OH^-

Answer 4

Metal aqua ion = Pale Pink Solution
[Mn(H₂O)6]²⁺

With OH− = Pale brown Precipitate
Mn(OH)2(H₂O)4

With excess OH− = no change

Question 5

Cu²⁺ :

Metal aqua ion

With OH^-

With excess OH^-

Answer 5

Metal aqua ion = Blue Solution
[Cu(H₂O)6]²⁺

With OH− = Blue Precipitate
Cu(OH)2(H₂O)4

With excess OH− = no change

Question 6

Cr³⁺ :

Metal aqua ion

With NH₃

With excess NH₃

Answer 6

Metal aqua ion = Violet Solution
[Cr(H₂O)6]3+

With NH3 = Green Precipitate
Cu(OH)3(H₂O)3

With excess NH3 = Purple Solution
[Cr(NH₃)₆]³⁺

Question 7

Fe²⁺ :

Metal aqua ion

With NH₃

With excess NH₃

Answer 7

Metal aqua ion = Green Solution
[Fe(H₂O)6]²⁺

With NH3 = Green Precipitate
Fe(OH)2(H₂O)4

With excess NH3 = no change

Question 8

Fe³⁺ :

Metal aqua ion

With NH₃

With excess NH₃

Answer 8

Metal aqua ion = Yellow Solution
[Fe(H₂O)6]3+

With NH3 = Brown Precipitate
Cu(OH)3(H₂O)3

With excess NH3 = no change

Question 9

Mn²⁺ :

Metal aqua ion

With NH₃

With excess NH₃

Answer 9

Metal aqua ion = Pale pink Solution
[Mn(H2O)6]²⁺

With NH3 = Pale brown Precipitate
Mn(OH)2(H2O)4

With excess NH3 = no change

Question 10

Cu²⁺ :

Metal aqua ion

With NH₃

With excess NH₃

Answer 10

Metal aqua ion = Blue Solution
[Cu(H2O)6]²⁺

With NH3 = Blue Precipitate
Cu(OH)2(H2O)4

With excess NH3 = Dark Blue Solution
[Cu(NH3)4(H2O)2]²⁺