Colours in Coordination Compounds

$\text{Statement I}$ :  [Ti(H₂O)₆]⁴⁺ is coloured while [Sc(H₂O)₆]³⁺ is colourless.
$\text{Statement II}$ : d - d transition is not possible in [Sc(H₂O)₆]³⁺

The correct order for the wavelengths of absorption in the visible region for the following is: ${\left[\text{Ni}{\left({\text{NO}}_{\text{2}}\right)}_6\right]}^{4-},{\left[\text{Ni}{\left({\text{NH}}_{\text{3}}\right)}_6\right]}^{2+},{\left[\text{Ni}{\left({\text{H}}_{\text{2}}\text{O}\right)}_6\right]}^{2+}$

Explain the composition and colour of ruby stone.

What determines the Colour of gemstones ?

What is the colour of ${\left[\mathrm{Ti} {\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$?

Which of the following complexes is expected to be colored?

The octahedral complex of a metal ion ${\mathrm{M}}^{3+}$ with four monodentate ligands ${\mathrm{L}}_1, {\mathrm{L}}_2, {\mathrm{L}}_3 \mathrm{and} {\mathrm{L}}_4$ absorb wavelengths in the region of red, green, yellow and blue, respectively. The increasing order of ligand strength of the four ligands is

${\left[\mathrm{S}\mathrm{c}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$ ion is

Which of the following compounds is not coloured?

What is the green gemstone called?

Cranberry glass is a red glass made by adding _____ salts to molten glass.

Which elements give the gemstone emerald its green colour?

How do gemstones get their colour?

Which of the following complex will not show colour? 

 What will be the increasing order of the ligand strength with three monodentate ligands ${\mathrm{L}}_1, {\mathrm{L}}_2 \mathrm{and}\mathrm{ }{\mathrm{L}}_3$ absorb wavelengths in the region of green, blue and red respectively. Choose the correct order for Homoleptic octahedral complexes of a metal ion $\mathrm{\prime }{\mathrm{M}}^{3+}\mathrm{\prime }.$

Which of the following compound show colour due to charge transfer?

The colour of ${\mathrm{VCl}}_4$ is due to:

Amongst ${\left[{\mathrm{TiF}}_6\right]}^{2-}, {\left[{\mathrm{CoF}}_6\right]}^{3-},{\mathrm{Cu}}_2{\mathrm{Cl}}_2 \mathrm{and} {\left[{\mathrm{NiCl}}_4\right]}^{2-}$, which are the colourless chemical species?
 

On adding concentrated $\mathrm{HCl}$, the colour of ${\mathrm{CoCl}}_{2_{\left(\mathrm{aq}\right)}}$ changes from reddish pink to deep blue. Which of the following complex ion gives blue colour in this reaction?

The correct order for the wavelengths of absorption in the visible region for the following coordination compounds is: ${\left[\mathrm{Ni}{\left({\mathrm{NO}}_2\right)}_6\right]}^{4-}, {\left[\mathrm{Ni}{\left({\mathrm{NH}}_3\right)}_6\right]}^{2+}, {\left[\mathrm{Ni}({\mathrm{H}}_2\mathrm{O}{)}_6\right]}^{2+}$.