# ws10adds08key - CH 302 Spring 2008 Worksheet 10b: More...

This preview shows pages 1–2. Sign up to view the full content.

CH 302 Spring 200 8 Worksheet 1 0 b : More Advanced Electrochemistr y Problems 1. (a) Calculate the mass of copper metal produced at the cathode during the passage of 2.50 amps of current through a solution of copper (II) sulfate for 50.0 minutes. Cu 2+ + 2e - Cu (reduction/cathode) 1 mol 2(6.02 x 10 23 )e - 1 mol 63.5 g 2(9.65 x 10 4 C) 63.5g 50.0 min x (60s/1 min) x (2.50C/s) = 7.50 x 10 3 C 7.50 x 10 3 C x (1 mol e - /9.65 x 10 4 C) x (63.5 g Cu/2 mol e - ) = 2.47 g Cu (b) What volume of oxygen gas (measured at STP) is produced by the oxidation of water at the anode in the electrolysis of copper(II) sulfate in part (a)? 2H 2 O O 2 + 4H + + 4e - (oxidation/anode) 1 mol 4((6.02 x 10 23 )e - 22.4 L 4(9.65 x 10 4 C) 7.50 x 10 3 C x (1 mol e - /9.65 x 10 4 C) x (22.4 L O 2 /4 mol e - ) = 0.435 L O 2 2. What is the E ° for the following electrochemical cell where Zn is the cathode? Zn | Zn 2+ (1.0 M ) || Fe 2+ (1.0 M ) | Fe E ° (Zn) = -0.76 E ° (Fe) = -0.44 E cell = E ° cathode - E ° anode = -0.76 – (-0.44) = -0.32 3. For the electrolysis of molten sodium bromide, write the two half-reactions and show write which electrode at which each occurs (cathode or anode). Two half-reactions:

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 04/12/2008 for the course CH 302 taught by Professor Holcombe during the Spring '07 term at University of Texas.

### Page1 / 2

ws10adds08key - CH 302 Spring 2008 Worksheet 10b: More...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online