Molar concentration or Molarity is a way to measure the concentration of a solution after some solute has been added to the solvent, the formula for Molarity is:
M = n/V
where:
M = molar concentration
n = number of moles
V = volume of the solution in Liters
In the question we are given the molarity and volume, let's add these information to our formula
0.6 M = n/2.5 L
n = 1.5 moles of Iodine should be added