Problem 2 - Prof Frazer and Lead Analysis (20 points) Professor Ronnie Frazer-Williams works at the Department of Chemis
Posted: Tue Dec 07, 2021 9:35 pm
a) (3 pts) Based on K, calculate the value of Gºds for the dissolution of Pb(NO3)(s) in water. Report the result with three significant figures and proper units. b) (6 pts) From the values of AG as and known thermodynamic quantities in the table above, calculate the missing values of AG and for Pb(NO12{s). Show work. c) (3 pts) Suppose the lichen accumulates lead in the form of solid lead(II) carbonate. Treatment of solid lead(11) carbonate with aqueous nitric acid results in spontaneous dissolution and formation of a clear aqueous solution and bubbles of gas. Write a chemical equation in molecular form that explains this process d) (4 pts) Based on the description of reaction (c) and its chemical equation, do you expect the AGeen and Asan to be positive or negative? Explain briefly. e) (4 pts) Analysis of Pb(NO3)2(aq) by atomic absorption involves the use of a special AAS instrument in which the solution is heated to a very high temperature in reductive atmosphere, fully vaporized, and the resulting vapor is irradiated by light. Atoms of lead absorb light of certain wavelengths, which are detected and quantified in the instrument. To ensure the correct analysis, the lead should be fully vaporized. Assuming that lead becomes elemental in the AAS furnace and using the thermodynamic values below, calculate the temperature required to create the vapor pressure of lead equal to 1.00 x 10 atm. Use Lecture 22 for examples of such calculations. Substance AH, kl/mol SJ/mol K Pb(g) Pb(1) 17 195 88.0 175.3