CHEMISTRY 133

Spring, 2015 Homework Set 3

Only Problems in Bold are Submitted for Grading

Set 3.1 - Complete for quiz on Apr. 23

Rubinson and Rubinson Text Ch. 11: 1, 3, 4, 5, 7, Harris Text, Ch. 21: 5, 10, 13a-b, e, 24, 28

Additional Problems:

1. In a 2.35 Tesla field, the magnetogyric ratios (g) for ³¹P is 1.08 x 10⁸ T^-1 s^-1.

a)  At what frequency does ³¹P absorb light?

b)  If a sample has 1.000000 x 10⁶ nuclei in the ground state, how many nuclei will be in the excited state?  How could the number of excited nuclei be decreased?

      (Hint: e^-x = 1 - x when x is small)

2.  1,2-dichloropropane (CH₃CH(Cl)CH₂Cl) is analyzed by ¹H NMR.  It is observed to have a jumbled multiplet (unclear number of split peaks) at 4.1 ppm, and simpler peaks at 3.6 and 1.6 ppm.

a) Indicate which protons are giving the signals at each peak.

b) Predict the splitting pattern (e.g. triplet) observed at 3.6 and 1.6 ppm.

Additional Problem Solutions

Set 3.2 - Complete for quiz on May 7 [Note: quiz is extra and students that take it will qualify to drop their two lowest quiz scores as opposed to

the lowest as mentioned in syllabus]
Harris Text, Ch. 22: 2, 7a, 17, 19, 22, 24, 26, 28, 31, 32, 38, 42, 43

Ch. 23: 3a, 5, 17, 20 and Ch. 24: 1a, 4, 15 (if time)

Additional Problems (pdf of problems due to graphics - note that that last two are optional for bonus points)