Molarity or molar concentration is a measure of the concentration of a chemical species, of a solute in a solution, using as units, number of moles, and volume in liters. The formula for Molarity is:
M = n/V
Where:
n = number of moles
V = volume in Liters, 1 Liter
But we need to find the number of moles, we will do so by using its molar mass, KI = 166g/mol and the given mass in the question, 500g grams
166g = 1 mol
500g = x moles
x = 3.012 moles
Now we can use the Molarity formula
M = 3.012/1
M = 3.012 M, this is the molar concentration of the solution, 2