Assume that the solubility of CaCl₂ at this temperature is 70.1 g CaCl₂/100.0 g of H₂O and that the van't Hoff factor for a saturated solution of CaCl₂ is i = 2.5. The K_f for water is 1.86C/m.

CaCl₂ is often used to melt ice on sidewalks. Could CaCl₂ melt ice at -21.0C?

What is the minimum amount of CaCl₂ that would be required to melt ice on sidewalks at the above temperature? Use 100.0 g of water as the amount of solvent.