1 / 14

Electrochemistry

Zn. ZnSO 4 (aq). CuSO 4 (aq). Zn. Cu. Electrochemistry. Electrochemistry. Battery – uses the energy from a redox reaction to produce an electric current and do work. Electrochemistry – the study of the interchange of chemical and electrical energy. Electrochemistry.

callum-gill
Download Presentation

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. Zn ZnSO4(aq) CuSO4(aq) Zn Cu Electrochemistry

  2. Electrochemistry • Battery – uses the energy from a redox reaction to produce an electric current and do work. • Electrochemistry – the study of the interchange of chemical and electrical energy.

  3. Electrochemistry 2 Types of electrochemical processes • The production of an electric current from a chemical (redox) reaction – battery, voltaic cell, galvanic cell. • The use of an electrical current to produce a chemical change (redox reaction). Call this electrolysis.

  4. Electrochemistry • How do we capture the energy? • Separate the oxidizing agent (electron acceptor) from the reducing agent (electron donor) • Requires the electron transfer to occur through a wire or an electric motor!

  5. Figure 18.1: Schematic for separating the oxidizing and reducing agents in a redox reaction. Why is there no flow of electrons here? 8H+ + MnO4- + 5e- Mn2+ + 4H20 ; Fe2+  Fe3+ + e-

  6. Figure 18.2: Electron flow. Build up of charges would require large amounts of energy Solutions must be connected to allow ions to flow 8H+ + MnO4- + 5e- Mn2+ + 4H20 ; Fe2+  Fe3+ + e-

  7. Figure 18.4: The salt bridge contains a strong electrolyte. Figure 18.4: The porous disk allows ion flow.

  8. Electrochemistry • Want to allow ions to flow but not mix the solutions • Electrons flow in the wire from reducing agent to oxidizing agent

  9. Electrochemical battery (galvanic cell) • A device powered by a redox reactions where the oxidizing agent is separated from the reducing agent so that the electrons must travel through a wire from reducing agent to oxidizing agent

  10. Electrochemical battery (galvanic cell) • Reducing agent loses electrons so it is oxidized • Electrode where oxidation occurs is called the anode • Oxidizing agent gains electrons and is reduced • Electrode where reduction occurs is the cathode

  11. Figure 18.5: Schematic of a battery. Anode - electrode where oxidation occurs Cathode – electrode where reduction occurs Electron flow anode to cathode oxidation to reduction

  12. Electrochemistry Go back to first cell with Zn and Cu and draw a voltaic cell. Label anode, cathode, and show direction of e- flow. Write out the two half reactions and then write out the complete reaction.

  13. Cu/Zn Voltaic Cell Cu2+ + 2e-  Cu Cathode/reduction Zn  Zn2+ + 2e- Anode/oxidation Cu2+ + Zn  Zn2+ + Cu Cu Zn SO42- Zn2+ Cu2+ Zn2+

  14. Electrochemistry

More Related