According to Le Chatelier's Principle, if you increase the starting concentration of Ca2+ in a solution, it would shift the equilibrium in a way to counteract the increase. In this case, we have the dissolution reaction of the salt Ca(IO3)2, which can be represented as:
Ca(IO3)2(s) ⇌ Ca2+(aq) + 2IO3-(aq)
Increasing the concentration of Ca2+ would shift the equilibrium to the left, reducing the overall amount of Ca2+ dissolved in the solution. Consequently, it would also decrease the amount of Ca(IO3)2 that dissolves, as the reaction tries to maintain equilibrium by reducing the concentration of Ca2+ ions.
To determine the exact quantitative effect of increasing the starting concentration of Ca2+ on the amount of Ca(IO3)2 that dissolves, you would need to know the equilibrium constant (K) for the dissolution reaction and the initial concentrations of Ca2+ and Ca(IO3)2. By using the equilibrium constant expression and the concentration changes due to the shift in equilibrium, you could calculate the exact change in the amount of Ca(IO3)2 that dissolves.