Colour of halide ions

Reply 1

iodide and chloride ions are colourless. The fact it gave two answers was because if chlorine and iodine were in an aqueuous solution you would get:
colourless/greenish-yellow solution to a brown/red-brown solution
If they were in gaseous and solid forms then you would get:
a greenish-yellow gas to a grey/black solid

Hope that helps. :P

Reply 2

Demolion

Iodide ions are colourless, Iodine molecules in solution are brown/red. Same for chloride/chlorine.

Reply 3

Excalibur

It's not the ions that have the colour, it's the elements.

Chlorine = green vapour (standard state), pale green in aqueous solution
Bromine = brown liquid (standard state), brown vapour, brown in organic solutions
Iodine =grey/black solid (standard state), violet vapour, brown in aqueous solution, violet in organic solution

So in your equation, we are not told whether Cl2 is in aqueous solution or is a gas or not. So it can be either a green-yellow solution or a greenish gas. The product formed is I2, which if it is a solid it would be a grey solid, and if it is in aqeous solution it would be brown.

Reply 4

Tes

Excalibur

Iodine =grey/black solid (standard state), violet vapour, brown in aqueous solution, violet in organic solution

I thought it was pink in organic solution?

Reply 5

sufiankane

i think it is pink, but i believe he is excalibur is referring to iodine in starch.

Reply 6

RMIM

BlakDog

I thought it was pink in organic solution?

Some tests for I2 (iodine)

1. Purple in organic solvents that contain no oxgen
2. Brown in organic solvents that do contain oxygen
3. no effect on litmus paper
4. turns starch solution blue-black.