Aqueous Ions Flashcards
Name 4 types of ions involved within this topic
Fe 3+ , Fe2+ , Cu2+, Al3+
What is the colour fe 2+ aqueous ion
Green solution
What is the colour of cu 2+ aqueous ions
Blue solution
What is the colour of fe3+ aqueous ions
Purple solution.
What is the colour of aluminium 3+ ions
Colourless solution
What is a coordinate bond
Shared pair of electrons that come from the same atom
Formula for hexa aqua complex ions for x
[X(H2O)6] n
Why is fe3+ more acidic than fe2+
Fe 3+ has a higher charge there greater charge density and is a smaller ion
Fe 3+ is more polarising so attracts lone pair on ligand of oxygen in water
This weakens O-H bond
So fe3+ complex releases more H+ ions
Fe 3+ and Al3+ in water
They act an acid ( proton acceptor ( 1-) )
[Al(H2O)6]3+ + H2O = [Al(H2O)5(OH)]2+ + H3O+
Reactions with a base such as NaOH
Salt + water and balance
[Fe(H2O)6]3+ + 3OH- = [Fe(H2O)3(OH)3] + 3H2O
[ Fe(H2O)6]2+ + 2OH- = [Fe(H2O)4(OH)2] + 2H2O
Reactions with NH3
Salt + NH4+ balanced
[Fe(H2O)6]2+ + 2NH3 = [Fe(H2O)4(OH)2] + 2NH4+
[Fe(H2O)6]3+ + 3NH3 = [Fe(H2O)3(OH)3] + 3NH4+
Excess NH3 on Cu 2+
[Cu(H2O)4(OH)2] + 4NH3 = [Cu(H2O)2(NH3)4]2+ + 2OH- + 2H2O
Reactions with Na2CO3 with 2+ ions
Forms salt and water balance
[Cu(H2O)6]2+ + CO32- = CuCO3 + 6H2O
Reactions with Na2CO3 with 3+ ions
Salt and H2O and CO3 and balance ( opposite )
2[Al(H2O)6]3+ + CO32- = 3CO2 + 3H20 + 2[Al(H2O)3(OH)3]
Reactions with Cl- ions (4)
4 cl- MAKE SURE CHARGE IS CORRECT
Salt + H20
[Fe(H2O)6]2+ + 4Cl- = (FeCl4)2- + 6H2O
