 Answer these five questions about a compound containing carbon, hydrogen, and fluorine.
NOTE: Parts (a) and (b) of this exercise can be answered independently of one another. Once part (c) has been answered, parts (d) and (e) can be answered independently of one another.
(a) The compound contains 37.5 % C, 3.15% H, and 59.3% F by mass. What is its simplest formula?
(b) When 0.298 g of the compound was heated to 50°C in an evacuated 125 mL flask it converted to a gas. The pressure was observed to be 750 mm Hg. What is the molar mass of the compound?
(c) Find the molecular formula of the compound.
(d) There are three isomers of the compound. Determine the Lewis structure and the molecular geometry around the carbon atom(s) of the isomer that has no dipole moment. What are the structures of the other two isomers?
(e) When the compound is burned in excess oxygen, the products are CF4(g), CO2(g), and H2O(l). Complete combustion of 0.398 g of the compound raised the temperature of 200 g of water in a calorimeter from 25.00°C to 32.40°C. Outline how you would solve for the Hf° (kJ/mol) of the compound.
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