Hey there!:
Molar mass FeCl3 => 162.2 g/mol
Mass of solute => 10.0 g
Number of moles:
n = mass of solute / molar mass
n = 10.0 / 162.2
n = 0.0616 moles of FeCl3
Volume in liters:
250.0 mL / 1000 => 0.25 L
Therefore:
Molarity = number of moles / volume
M = 0.0616 / 0.25
Molarity = 0.2464 M
Hope that helps!
