Question

According to http://teaching.shu.ac.uk/hwb/chemistry/tutorials/molspec/beers1.htm
Beer's law does not apply at high concentrations.
Is there another law to model behavior at high concentrations? Do different solutes absorb light similarly at high concentrations?

Answer 1

Is there another law to model behavior at high concentrations i don't think soo any law is there which work at higher concentration!!
and different solutes absorb light similarly at high concentrations it s not true statement i can say

Answer 2

nope, you gotta dilute your solution. Beer's law deviates form linearity at very high or very dilute concentrations. And similarly, the instrument (spectrophotometer) loses linearity after a certain concentration.

I would say that they will appear to absorb light similarly at high concentrations simply because you're basically blocking the light, so the instrument will pick up the same signal.
But in dilute solutions they won't, each species absorbs light most efficiently at a given wavelength(s) hence the molar absorption/absorptivity/extinction coefficient.

Answer 3

Beers law is only obeyed at dilute solutions.