2. Freezing point depression: Vapona is the ingredient found in flea collars and pesticide strips. A sample of 0.347g of vapona was melted together with 35.0g of camphor, and this mixture was cooled to give a solid. The solid was pulverized and its melting point was found to be 35.99C. Using the identical thermometer, pure camphor was found to melt at 37.68C. For camphor, Kf=37.7C/m. What is the molar mass of vapona? 3. Boiling point elevation: A solution of 8.32g of PABA (para-aminobenzoic acid), a common sunscreen agent, in 150. g of chloroform boiled at 62.62C. At the same pressure and with the same thermometer, pure chloroform boiled at 61.15C. What is the formula weight of PABA ? For chloroform, Kb=3.63C/m. 4. Fractional crystallization: The solubility of two salts are given in the table below: Suppose you are given a 50/50(m/m) mixture of RbCl/NaL. a. Will fractional crystallization in water be effective? Why or why not? b. The table above suggests another way to separate the salts. What is it? Is it more effective than the method in (a)