Aqueous ions

Question 1

Reactions of aqueous ions with CO3 2- ions
-2

Answer 1

[M(III)(H2O)6]2++CO3,2->MCO3+6H2O

2[M(III)(H2O)3+,+3CO3,2–>2[M(H2O)3(OH)3]+3CO2+3H2O

Question 2

Dropwise NH3 and NaOH

Answer 2

M 2+
[M(H2O)6]2+,+2NH3->[M(H2O)4(OH)2]+2NH4+

[M(H2O)6]2+,+2OH-,->[M(H2O)4(OH)2]+2H2O

M 3+
[M(H2O)6]3+,+3NH3->[M(H2O)4(OH)2]+3NH4+

[M(H2O)6]3+,+3OH-,->[M(H2O)3(OH)3]+3H2O

Question 3

Ligand substitution reactions of aqueous ions

Answer 3

excess NH3
[Cu(H2O)6]2+,+4NH3->[Cu(NH3)4(H2O)2]2+,+2H2O+2OH-
concentrated HCl
[Cu(H2O)6]2+,+4Cl-,->[CuCl4]2-+6H2O

excess NaOH
[Al(H2O)3(OH)]+OH-,->[Al(H2O)2(OH)4]-+H2O

Question 4

Why does [Al(H2O)6]3+ Appear colourless?

Answer 4

No d electrons in Al3+

Question 5

Why does [Fe(H2O)6]3+ often appear brown instead of purple

Answer 5

because of the Prescence of small amounts of [Fe(H2O)5(OH)]2+