[Ryedan114]

A drop of concentrated nickel(II) sulfate solution, which is green, is placed on moist
filter paper on a microscope slide and the ends of the slide are connected to a 24 V DC
power supply. After ten minutes,
A a blue colour has moved towards the negative terminal and a yellow colour
towards the positive terminal.
B a blue colour has moved towards the positive terminal and a yellow colour
towards the negative terminal.
C a green colour has moved towards the negative terminal but there is no other
visible change.
D a green colour has moved towards the positive terminal but there is no other
visible change

It's D: I know S04 is 2- Charge, and Nickel is 2+. But why is Nickel Green? And why does S042- have no visible colour? Shouldn't it move to the Positive terminal?

[TheStudent.]

(Original post by Ryedan114)
A drop of concentrated nickel(II) sulfate solution, which is green, is placed on moist
filter paper on a microscope slide and the ends of the slide are connected to a 24 V DC
power supply. After ten minutes,
A a blue colour has moved towards the negative terminal and a yellow colour
towards the positive terminal.
B a blue colour has moved towards the positive terminal and a yellow colour
towards the negative terminal.
C a green colour has moved towards the negative terminal but there is no other
visible change.
D a green colour has moved towards the positive terminal but there is no other
visible change

It's D: I know S04 is 2- Charge, and Nickel is 2+. But why is Nickel Green? And why does S042- have no visible colour? Shouldn't it move to the Positive terminal?

Nickel is a transition metal, found in the d-block of a periodic table, and one of the many properties of a transition metal is that they're able to form coloured ions. Shouldn't what move to the positive terminal?

I can't explain why its green though i'd refer you to my sister who's been said to be able to see things at a molecular level, but she's not here at the moment

S042- has no visible colour, becauseeeeeee using the same logic, its not a transition metal thats a complete guess but hey i'm trying lol