CHEMISTRY 133

Spring, 2016 Homework Set 2

Only Problems in Bold are Submitted for Grading

Set 2.1 - Complete for quiz on Mar. 10

Harris Text: Ch. 13: 16, 19, 28, 36; Ch. 14: 2, 20; Ch. 17: 3, 4

Additional Problems:

1.  A cell is made containing 0.10 M NaBr(aq), Ag(s), and AgBr(s) and when coupled with a Cu²⁺/Cu(s) cell under standard conditions with Cu(s) in the cathode, the measured voltage is 0.247 V.  Given that the standard reduction potential for Cu + 2e^- ↔ Cu(s) and Ag + e^- ↔ Ag(s) are 0.339 V and 0.799 V, respectively, calculate the equilibrium constant for the reaction: AgBr(s) ↔ Ag⁺(aq) + Br^-.  Assume the cell is at 25°C.

2.  An electrochemical cell (see notation and diagram below) is made to determine the concentration of tin (Sn²⁺) in an industrial process stream:

SnO₂(s)|Sn²⁺ (X M), HNO₃ (0.10 M)|| NaCl (0.10 M)|Ag(s), AgCl(s)

If the cell potential is measured (connecting the Ag/AgCl electrode to the positive end of a voltmeter) and found to be 0.380 V, determine the concentration of tin in the cell.  Assume the cell temperature is 25°C and use E° values listed in Appendix H as needed.

Set 2.2 - Complete for quiz on March 29 
Harris Text: Ch. 17: 11, 16, 24, Ch. 19: 1, 3-6, 10, 11, 13, 28

Additional Problem:

Problem 1.  (this has graphics so I’m linking to a pdf )

2.  Calculate the ratio of Ni atoms present in an excited state responsible for emission of light at a wavelength of 231 nm to those in the ground state in an inductively coupled plasma if the temperature is 5200 K.  g*/g_o = 3.

Set 2.3 - Complete for Exam 2 on April 7
Ch. 20, 1, 2, 4, 7, 14, 21   -  No additional Questions