as you know critical angle depends on refractive index. The refractive index in turn depends on the phase velocity of that particular light. And phase velocities are different for different colours. So critical angle is related to color of light.
Aswin Krishnan answered this
whom do i have 2 believe
Vishnu answered this
critical angle depends only on the angle of incidence and refractive index of the medium
Abhirami Biju answered this
i think it depends on the colour of light bcoz it depends on the refractive index then it wil depend on the wavelength thus on the color also ..but im not sure