Transition Metals (Chemistry)

Question 1

What colour is [ Fe(H2O)6 ]^+2?

Answer 1

pale green solution

Question 2

What colour is [ Fe(OH)2(H2O)4 ] or Fe(OH)2?

Answer 2

green ppt

Question 3

What colour is [ Fe(H2O)6 ]^+3?

Answer 3

pale yellow solution

Question 4

What colour is [ Fe(OH)3(H2O)3 ] or Fe(OH)3?

Answer 4

Orange ppt

Question 5

What is added to [ Fe(H2O)6 ]^+2 to make [ Fe(OH)2(H2O)4 ]

Answer 5

NH3 (aq) or NaOH
pale green solution to green precipitate

Question 6

What is added to [ Fe(H2O)6 ]^+3 to make [ Fe(OH)3(H2O)3 ] and what is the colour change?

Answer 6

NH3 (aq) or NaOH
pale yellow solution to orange ppt

Question 7

What colour is [ Cr(H2O)6 ]^+3?

Answer 7

violet solution

Question 8

What colour is [ Cr(OH)3(H2O)3 ] or Cr(OH)3 ?

Answer 8

grey/green ppt

Question 9

What colour is [ Cr(NH3)6 ]^3+?

Answer 9

purple solution

Question 10

What colour is [ Cr(OH)6 ]^3-?

Answer 10

green solution

Question 11

What is added [ Cr(H2O)6 ]^3+ to make [ Cr(OH)3(H2O) ] and what is the colour change?

Answer 11

NaOH or a few drops of NH3
Violet solution to grey/green ppt

Question 12

What is added [ Cr(H2O)6 ]^3+ to make [ Cr(NH3)6 ]^3+ and what is the colour change?

Answer 12

Excess NH3
violet to purple solution

Question 13

What is added to[ Cr(H2O)6 ] to make [ Cr(OH)6 ]^3- and what is the colour change?

Answer 13

Excess NaOH
violet to green solution

Question 14

What colour is [ Mn(H2O)6 ]^2+?

Answer 14

pale pink solution

Question 15

What colour is [ Mn(OH)2(H2O)4 ] / Mn(OH)2?

Answer 15

pale brown ppt

Question 16

What is added [ Mn(H2O)6 ]^2+ to make [ Mn(OH)2(H2O)4 ] and what is the colour change?

Answer 16

NaOH or a few drops of NH3
pale pink solution to pale brown ppt

Question 17

What colour is [ Cu(H2O)6 ]^2+?

Answer 17

blue solution

Question 18

What colour is [ Cu(OH)2(H2O)4 ]?

Answer 18

pale blue ppt

Question 19

What colour is [ Cu(NH3)4(H2O)2 ]^2+?

Answer 19

deep blue solution

Question 20

What colour is [ CuCl4 ]^2-?

Answer 20

yellow solution

Question 21

What is added [ Cu(H2O)6 ]^2+ to make [ Cu(OH)2(H2O)4 ] and what is the colour change?

Answer 21

a few drops of NH3 and NaOH
blue solution to pale blue ppt

Question 22

What is added [ Cu(OH)2(H2O)4 ] to make [ Cu(NH3)4(H2O)2 ]^2+ and what is the colour change?

Answer 22

excess NH3
pale blue ppt to deep blue solution

Question 23

What is added [ Cu(H2O)6 ]^2+ to make [ CuCl4 ]^2- and what is the colour change?

Answer 23

Cl-
blue solution to yellow solution

Question 24

what are the three shapes of complex ions with example?

Answer 24

octahedral - [Fe(OH)2(H2O)4]
tetrahedral - [Cu(Cl)4]^2-
square planar - [Pb(NH3)2(Cl)2]

Question 25

what are the three types of reactions undergone by complex ions and what are the changes show in each?

Answer 25

precipitation - coloured ppt
ligand substitution - colour of complex ion changes
redox - colour change

Question 26

Give an example of redox with transition metals?

Answer 26

Fe^3+ +2I^- –> Fe^2+ the I2

Question 27

Give an example of ligand substitution with transition metals?

Answer 27

[Cu(H2O)6]^2+ + excess NH4 –> [Cu(NH3)4(H2O)2]^2 + 4H2O

Question 28

Give an example of precipitation with transition metals?

Answer 28

[Cu(H2O) + NaOH/(a few drops) NH3 –> (Cu(OH)2(H2O)4]

Question 29

define a transition element

Answer 29

an element with a least one ion with a partially filled d-orbital

Question 30

define a complex ion

Answer 30

a central metal ion surrounded by ligands

Question 31

define a ligand

Answer 31

a molecule with a lone pair of electrons that can form a coordinate/dative bond

Question 32

what is the colour change of [Co(H2O)6]^2+ to [Co(Cl)4]^2-

Answer 32

pink to blue solution