[yin323]

I am doing a project about the colour in transition metal complex.
But how's it related to our daily life?
I wanna find some application of " the color of transition metal" , which is based on the principle of the ligand exchange of the metal complex.
Could you guys give me some ideas about this topics?
Thanks so much!!! 

[DevaDevil]

Best known example (I think) of the use of changeing colors in transition-metal ions are the Chromium dyes.
Examples:
Cr₂O₃ - "chrome green"
PbCrO₄ - "chrome yellow"
Cr added to Al₂O₃ makes a ruby red

[yin323]

Best known example (I think) of the use of changeing colors in transition-metal ions are the Chromium dyes.
Examples:
Cr₂O₃ - "chrome green"
PbCrO₄ - "chrome yellow"
Cr added to Al₂O₃ makes a ruby red

The example needs to relate to the exchange ligand of transition metal >_<

But anyway, thanks a lot!!

[FeLiXe]

the typical expample is a cobalt complex. it's either pink or blue depending on air humidity.

[mdlhvn]

Right, it is a typical example. CoCl2 is used as an indicator, the drying agent is blue when still active, pink when exhausted, corresponding to the anhydrous and hydrated forms of CoCl2, respectively. Cobalt chloride paper is likewise used to detect the presence of water. Here Cl ligands is replaced by water ligands
 

[Ψ×Ψ]

eriochrome black T!  still used by environmental labs to determine water hardness.

[mdlhvn]

eriochrome black T!  still used by environmental labs to determine water hardness.

-----------> What do you mean? eriochrome black T! is an indicator

[green-goblin]

eriochrome black T!  still used by environmental labs to determine water hardness.

-----------> What do you mean? eriochrome black T! is an indicator

It turns red when bound to a metal so can be used detect calcium in water and hence  indicate its hardness