Human or environmental risk to chemical exposure has to consider not only the direct exposure to the specific chemical but also the risk of exposure to any reaction by-product. for example, sulfur tetrafluoride (sf4) is a useful chemical reagent in synthesis, and is produced by the reaction of sulfur dichloride with sodium fluoride according to the following reaction: 3sc12(g) + 4naf(s) = sf4(g) + s2c12(g) + 4nacl(s) (1) the physiological by-products of sf4 make it a significantly toxic compound because it reacts with water in the lungs to form hydrofluoric acid: sf4(g) + 2h2o(l) → so2(g) + 4hf(g) (2) a) what is the shape of the sulfur-containing molecules, sc12, sf4 and so2 around the central sulfur atom? in each case, estimate the bond angles around the sulfur atom. b) the reaction is initiated in a sealed 5.0 l reaction vessel containing 240 kpa of sc12(g) and 100.0 g of naf(s) at a temperature of 70°c. calculate the partial pressure of sf4(g) present once the reaction reaches equilibrium, assuming ideal gas behaviour. c) the experimentally measured partial pressure of sf4(8) present at equilibrium is, in fact, lower than that predicted for an ideal gas. explain this deviation from ideal behaviour based on the structure of sf4. d) both gases produced in reaction (2) are water soluble and undergo acid-base chemistry with the water in the lungs. what are the acid-base reactions that each gas undergoes? e) challenge question (harder than expected, but possible with chemistry 1a knowledge). to test the impact of sf4, the gases in the 5 l flask from part b) were extracted. the temperature was lowered to condense the s2cl2 and scl2, and the sf4(g) extracted. the gas was then passed through 1.00 l of water. what is the ph of the final solution, assuming all the gas dissolves? data: pka (hf) = 3.1; pk. (h2so3) = 1.89 a_h° (kj-moll) so (jk-moll) sf4(g) -763.2 299.6 -16.7 327.2 s2cl2(g) scl2(g) -17.6 281.6 -575.4 naf(s) nacl 51.2 72.1 411.1