Do some colors absorb ultraviolet light?

No color absorbs any other color. Colors of light are just (mostly) wavelengths that we perceive. read more

Lots of substances, including many pigments and dyes, absorb ultraviolet light. The color we perceive is unaffected by whether ultraviolet is absorbed ore reflected, it depends only on what happens to the visible light. Frequently, substances that absorb violet light strongly (e.g., yellow substances) will have at least some absorbance in the near UV. read more

The molecule in acid solution is colorless because our eyes can't detect the fact that some light is being absorbed in the ultra-violet. However, our eyes do detect the absorption at 553 nm produced by the form in alkaline solution. 553 nm is in the green region of the spectrum. read more