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Chemistry

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1. During a Monsanto's acetic acid synthesis with Rhodium, what is the purpose of the HI in the reaction?  During the 4 steps of the reaction, what are the factors which keep the catalytic cycle turning?

2. Turnover frequency during the above process is the number of reactants molecules "turned over" per second at a given concentration of catalyst.  If one Rhodium catalyst has iodines as ligands (TOF 10.4x104 hz) and one uses acetates (TON 5.2x104 hz), which would be preferred in terms of performance?, if the iodine was twice the cost of the acetate, would you prefer it over the acetate?

 

3. During the oxidation of SO2 to SO3 on vandium oxide, what happens on the surface of the vanadium oxide catalyst? (draw me a diagram with the chemistry which is occuring) Describe the process?  Would you expect a homogenous catalysts to be more or less efficent for the oxidation? why?  

 

4. During the oxidation of SO2 to SO3 on vanadium oxide, sometimes the vanadium is converted to vanadium sulfide.  What impact would you expect this to have on the reactivity of the catalyst?  Why?

 

5. For over 100 years the Haber-Bosch process has been used for the production of ammonia with very few modifications.  a) Why is it so inefficient, b) what is meant by a process being inefficient?

 

6. When a company is looking to use a commodity acid to acidify the reaction mixture to pH 3, they typically pick a weaker form of sulfuric acid to HCl, HNO3, or H3PO4.  Why would you not pick one of the other ones?  This assumes that the acid is just a pH adjuster and not a chemical reactant.

 

7. Using an ideal stoichiometric reaction, a) what would be the atom efficiency of a LeBlanc process for making soda ash, b) What about the Solvay process?

 

8. Given the nine planetary boundaries, which ones does phosphate production/use figure into? Why?

 

9. How would you try and separate out the metal elements in the mineral Monazite (which is 14.46 %  La, 29.17 %  Ce, 4.83 %  Th, 12.89 %  P, 12.01 %  Nd, and 26.64 %  O)?  Assuming that Monazite is only 5% of the ore, how much Nd would you get from 1 ton of ore?