Final answer:
Type II De-icing Fluid is a glycol-based solution used on aircraft to remove and prevent ice formation without corroding metal surfaces, contrary to ionic de-icing agents used on roadways.
Step-by-step explanation:
Type II De-icing Fluid is typically a heated and sprayed glycol-based solution used for de-icing aircraft before take-off. Unlike ionic compounds such as rock salt and its group 2 analogs (calcium chloride and magnesium chloride), which are corrosive to metals and thus not suitable for de-icing planes, glycols like ethylene or propylene glycol don't corrode metal surfaces. These covalent compounds lower the freezing point and elevate the boiling point of the fluid, making them ideal for maintaining aircraft safety in icy conditions.
While ionic compounds can effectively depress the freezing point for de-icing roadways, their corrosive properties make them unsuitable for aviation applications, where Type II De-icing Fluid plays a crucial role.