Aqueous Ions Flashcards
What happenes if you put a transition metal into salt solution
It will dissolve and become its ions
the metal ion is then surrounded by 6 water ligands
What colour is the complex [Fe(H2O)6]2+
Green
central metal charge: Fe2+
What colour is the complex [Cu(H2O)6]2+
Blue
central metal charge: Cu2+
What colour is the complex [Fe(H2O)6]3+
Purple
- often brown due to presence of small amounts of [Fe(H2O)5(OH)]2+
central metal charge: Fe3+
What colour is the complex [Al(H2O)6]3+
Colourless
central metal charge: Al3+
What does Amphoteric mean
can act as an acid AND a base
what metal is an amphoteric
Aluminium
What is the equation and observation for the addition of NaOH dropwise to [Cu(H2O)6]2+
[Cu(H2O)6]2+ + 2OH- > Cu(H2O)4(OH)2 + 2H2O
blue solution forms a blue ppt
What type of reaction is the addition of NaOH to a complex
acid base reaction
What is the equation and observation for the addition of excess NaOH to [Cu(H2O)6]2+
Same equation as dropwise
No further change
What is the equation and observation for the addition of NaOH dropwise to [Fe(H2O)6]2+
[Fe(H2O)6]2+ + 2OH- > Fe(H2O)4(OH)2 + 2H2O
green solution forms green ppt
What is the equation and observation for the addition of excess of NaOH to [Fe(H2O)6]2+
Same equation as drop wise
No further change
What is the equation and observation for the addition of NaOH dropwise to [Fe(H2O)6]3+
[Fe(H2O)6]3+ + 3OH- > Fe(H2O)3(OH)3 + 3H2O
brown solution forms a brown ppt
What is the equation and observation for the addition of excess NaOH to [Fe(H2O)6]3+
Same equation as with dropwise
No further change
What is the equation and observation for the addition of of NaOH dropwise to [Al(H2O)6]3+
[Al(H2O)6]3+ + 3OH- > Al(H2O)3(OH)3 + 3H2O
colourless solution forms white ppt
What is the equation for the addition of excess NaOH to [Al(H2O)6]3+
Al(H2O)3(OH)3 + OH- > [Al(H2O)2(OH)4]- + H2O
What is the equation and observation for the addition of NH3 dropwise to [Cu(H2O)6]2+
[Cu(H2O)6]2+ + 2NH3- > Cu(H2O)4(OH)2 + 2N+H4
blue solution forms a blue ppt
What is the equation and observation for the addition of conc NH3 to [Cu(H2O)6]2+
ligand substation reaction
Cu(H2O)4(OH)2 + 4NH3 > [Cu(H2O)2(NH3)4]2+ + 2H2O + 2OH-
Blue ppt forms dark blue solution
What happens to Fe(H2O)4(OH)2 when left in standing air
it is oxidised to Fe(H2O)3(OH)3 and forms a brown ppt
What is the equation and observation for the addition of NH3 dropwise to [Fe(H2O)6]2+
[Fe(H2O)6]2+ + 2NH3- > Fe(H2O)4(OH)2 + 2N+H4
What is the equation and observation for the addition of conc NH3 to [Fe(H2O)6]2+
Same as equation with dropwise
No further change
What is the equation and observation for the addition of NH3 dropwise to [Fe(H2O)6]3+
[Fe(H2O)6]3+ + 3NH3 > Fe(H2O)3(OH)3 + 3N+H4
Green solution forms green ppt
What is the equation and observation for the addition of conc NH3 to [Fe(H2O)6]3+
Same as the equation with dropwise
No further change
What is the equation and observation for the addition of dilute NH3 dropwise to [Al(H2O)6]3+
[Al(H2O)6]3+ + 3NH3 > Al(H2O)3(OH)3 + 3N+H4
Colourless solution forms white ppt
What is the equation and observation for the addition of conc NH3 to [Al(H2O)6]3+
Same as the equation with dropwise
No further change
What is the equation and observation for the addition of CO3 dropwise to [Cu(H2O)6]2+
[Cu(H2O)6]2+ + CO3^2- > CuCO3 + 6H2O
Blue solution forms blue/green ppt
What is the equation and observation for the addition of CO3 dropwise to [Fe(H2O)6]2+
[Fe(H2O)6]2+ + CO3^2- > FeCO3 + 6H2O
Green solution forms green ppt
What is the equation and observation for the addition of CO3 dropwise to [Fe(H2O)6]3+
Acid base reaction
2[Fe(H2O)6]3+ + 3CO3^2- > 2Fe(H2O)3(OH)3 + 3H2O + 3CO2
Brown solution forms brown ppt
Effervescence due to CO2
What is the equation and observation for the addition of CO3 dropwise to [Al(H2O)6]3+
Acid base reaction
2[Al(H2O)6]3+ + 3CO3^2- > 2Al(H2O)3(OH)3 + 3H2O + 3CO2
Colourless solution forms white ppt
Effervescence due to CO2
Why do Fe3+ and Al3+ complexes have different reaction with CO3
3+ ions are more acidic
- Fe3+ & Al3+ are smaller ions w/ a greater charge
- O-H bond in water are more polarised
- More h+ are released
What is the equation and observation for the addition of conc HCl dropwise to [Cu(H2O)6]2+
Ligand substitution reaction
[Cu(H2O)6]2+ + 4Cl- > [CuCl4]^2- + 6H2O
Blue solution forms yellow/green ppt
What is the equation and observation for the addition of conc HCl dropwise to [Fe(H2O)6]2+
Ligand substitution reaction
[Fe(H2O)6]2+ + 4Cl- > [FeCl4]^2- + 6H2O
Green solution forms green ppt
What is the equation and observation for the addition of conc HCl dropwise to [Fe(H2O)6]3+
Ligand substitution reaction
[Fe(H2O)6]3+ + 4Cl- > [FeCl4]- + 6H2O
Brown solution forms brown ppt
What is the equation and observation for the addition of conc HCl dropwise to [Al(H2O)6]3+
Ligand substitution reaction
[Fe(H2O)6]2+ + 4Cl- > [FeCl4]- + 6H2O
Colourless solution forms white ppt
What is NaCO3
a weak base
