This is again determinism verses non determinism.
On a macroscopic level if enough data can be collected, or if the system can be modeled, or if the intital conditions mapped,,,then yes reality can be partially determined. Chance is alot like probability IMO, probabilities do not affect outcomes, but do provide a confidence interval. Inital conditions can not be duplicated exactley down the the very atom. So IMO science is left with guesses. Very good guesses mind you but thats about all. On a quantum level (microscopically) there seems to be a measure of true randomness ie...as others mentioned radioactive decay. So does chance exist? Yes ...probabilities exist too IMO, But what does that matter? What is going to happen is going to happen. Does free will exist? That again depends on what your personal definition of free will . Some say if you decide to wear black instead of blue you have excercised a choice. But ardent determinist will point out that the choice is simply a cascade on the infinate order of cause and effect that eventually 'caused' your choice. The butterfly effect on the extreme magnitude...A butterfly in Japan flaps its wings which cause a ripple of air current to move some water which propagates into a wave which moves a twig to detonate a water mine, which sends shrapnel out into the land which disturbs a bird that flaps unto your window, the bird is black and subconciously when you awake the next morning you choose to wear black.
PS...it is all moot because first off initial conditions can never be exact. And secondly at the present human understanding of physical reality is still incomplete.IMO
"One is punished most for ones virtues" Fredrick Neitzche