ionic compounds - What is the colour of chromium(III) chloride solution?

I had a question asking about the colour of the solution of chromium(III) chloride in my exam, all my colleagues have different answers, I couldn't find any exact answer after searching!

Answer

The color of the solution may vary as long it is not in equilibrium.

According Bjerrum and Bjerrum¹ a $\ce{1\mathrm{M}}$ chromium (III) chloride solution in equilibrium at 25° C contains about 13% monochloro and 85% hexaqua ions.

The absorption spectrum published shows minima at $\ce{480 \mathrm{nm}}$ (blue) for the hexaqua and $\ce{510 \mathrm{nm}}$ (green) for the monochloro complex.

          

When we integrate over the spectrum we get the following colors.

          

However, it should be noted that the colors vary with spectral optical depth (concentration, thickness of the medium).

_{1 Bjerrum, M.J. and Bjerrum, J., 1990. Estimation of Small Stability Constants in Aqueous Solutions. The Chromium(III) Chloride System. Acta Chem. Scand. 44: 358-363.}