Determine the relationship between the melting point of an impure substance to that of a pure substance. A.The melting point of the impure substance compared to the pure substance cannot be determined. B. The melting point of the impure substance would be the same as that of the pure substance. C. The melting point of the impure substance would be higher than that of the pure substance. D.The melting point of the impure substance would be lower than that of the pure substance.