Transition Metals Tests

Question 1

What colour is the precipitate of (Cr(H2O)6)^3+ and what colour is it in NaOH and NH3

Answer 1

Blue green
Green (Cr(OH)6)^3- (aq)
Not soluble so stays same as start

Question 2

What colour is the precipitate of (Mn(H2O)6)^2+ and what colour is it in NaOH and NH3

Answer 2

White which darkens to brown/black on standing
Not soluble
Not soluble

Question 3

What colour is the precipitate of (Fe(H2O)6)^2+ and what colour is it in NaOH and NH3

Answer 3

Green
Not soluble
Not soluble

Question 4

What colour is the precipitate of (Fe(H2O)6)^3+ and what colour is it in NaOH and NH3

Answer 4

Brown
Not soluble
Not soluble

Question 5

What colour is the precipitate of (Co(H2O)6)^2+ and what colour is it in NaOH and NH3

Answer 5

Blue
Not soluble
Yellow (changes to brown on standing) (Co(NH3)6)^2+ (aq)

Question 6

What colour is the precipitate of (Ni(H2O)6)^2+ and what colour is it in NaOH and NH3

Answer 6

Green
Not soluble
Blue (Ni(NH3)6)^2+ (aq)

Question 7

What colour is the precipitate of (Cu(H2O)6)^2+ and what colour is it in NaOH and NH3

Answer 7

Blue
Soluble
Deep/dark blue (Cu(NH3)4(H2O)2)^2+ (aq)