1 / 22

Review- Electrochemistry

Review- Electrochemistry . How it works. Partner “green” will discuss a strategy on how to complete the problem Then, Partner “blue” will comment on the strategy and add any further details needed and write down the steps to solving the problem, without actually solving it.

qabil
Download Presentation

Review- Electrochemistry

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Review- Electrochemistry

  2. How it works • Partner “green” will discuss a strategy on how to complete the problem • Then, Partner “blue” will comment on the strategy and add any further details needed and write down the steps to solving the problem, without actually solving it. • Finally, Partner “red” will use the strategy that the other two partners outlined to actually complete the problem. • Roles will be rotated each problem

  3. Problem 1 (Blue, green, red) • How many grams of aluminum can be deposited if 31,500 coulombs of electricity pass through an aluminum nitrate solution?

  4. answer • 2.94 grams

  5. Problem 2: (green, red, blue) • Balance the following equation AsH3 + ClO3-  H3AsO4 + Cl- (acidic soln)

  6. answer • 3 AsH3 + 4ClO3-  4Cl- + 3H3AsO4

  7. Problem 3 (red, blue, green) • If 10.0 amperes of current flow for 20.0 minutes through a solution of copper (II) nitrate, how many moles of copper are deposited?

  8. answer • 0.062 moles

  9. Problem 4: (red,blue,green) • Water was electrolyzed for 5.61 minutes using a constant current of 0.513 amperes. Calculate the volume, in liters, of hydrogen gas produced at 298 K and 1.00 atm.

  10. answer • 0.022 L

  11. Problem 5 • Calculate Ecell for the reaction that occurs when a standard voltaic cell of Zn/Zn2+ and Al /Al3+ have concentrations of 0.100 M and 0.0500M respectively.

  12. answer • 0.896 V

  13. Problem 6: (red, green, blue) • 5.77 g of zinc is deposited at the cathode when a current of 7.1 amperes passes through an electrolytic cell for 40. minutes. What is the oxidation state of the zinc in the aqueous solution?

  14. answer • Zn 2+ • Should find that there are 0.088 moles of Zn and 0.17658 moles of electrons- which must mean that there need to be 2 moles of electrons per mole of Zn meaning that the oxidation state is 2.

  15. Problem 7: • Balance the following reaction: N2O4 + Br- NO2- + BrO3- (basic soln)

  16. answer • Br- + 6OH- + 3 N2O4 6 NO2- + BrO3- + 3H2O

  17. Problem 8: (green, red, blue) • Choose the best reducing and oxidizing agent from the following: • Cu(s) • Zn(s) • Ag+ • Al3+ • F- • F2

  18. answer • Strongest oxidizing agent: F2 (it itself is reduced) • Strongest reducing agent: Zn (it itself is oxidized)

  19. Problem 9: (red, blue, green) • All of the following substances can act as oxidizing agents except: • H2O2 • Cr2O72- • MnO4– • IO3– • Br –

  20. answer • Br-

  21. Problem 10: (blue, red, green) • Calculate K(the equilibrium constant) at 298K for the following reaction: Cl2 (g) + 2I- (aq)  2 Cl-(aq) + I2(s)

  22. answer • E⁰=0.83V • K=1.2x1028 or 1.1x1028

More Related