slide1 n.
Skip this Video
Loading SlideShow in 5 Seconds..
Redox #’s 1-5 PowerPoint Presentation
Download Presentation
Redox #’s 1-5

Loading in 2 Seconds...

  share
play fullscreen
1 / 9
Download Presentation

Redox #’s 1-5 - PowerPoint PPT Presentation

ciara-white
70 Views
Download Presentation

Redox #’s 1-5

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Redox #’s 1-5 #1) The reaction absorbs energy, therefore it is electrolytic (A). #3) Electrolysis requires an external power source (A). #4) Reduction occurs at the cathode and the positive ion will migrate towards the negatively charged electrode (A). #5) AN OX → RED CAT (D)-oxidation at anode.

  2. #6) Electrolysis, negative electrode → cathode → Reduction → Gain of e-’s NaCl(aq) → Na+ + Cl- (D) Cl0 → Cl- + 1e- #7) From the reaction Pb0 + Cu+2 → Pb2+ + Cu0 The lead (Pb) is oxidized (anode) and the copper is reduced (cathode). FATCAT-Flow from anode to cathode. OR Pb(s) to Cu(s)

  3. 4 + 3e- 3 4e- + Formation of Aluminum Oxide #8) • Al0 → Al3+ O20 → O-2 OR4Al0 → 4Al3+ +12e- OR3O20 + 12e- → 6O2- b. The oxidation # in Al2O3 is -2.

  4. 2e- lost 3 3 Zn0 → Zn2+ Cr3+ → Cr0 3 + 2e- OR3Zn0 → 3Zn2+ +6e- 2 3e- + OR2Cr3+ + 6e- → 2Cr0 Zinc Chromium Electrochemical Cell Increase in oxidation # means Oxidation. Zn0 + Cr3+→ Zn2+ + Cr0 2 2 A reduction (dec.) in oxidation # means umm….. 3e- gained

  5. Problems 9-14 #9) Cr3+ + 3e- → Cr0 #10) The Cr3+ gains electrons The Zn0 loses electrons #11) Nothing happens to the PROTONS, redox is the loss/gain of ELECTRONS ONLY!!! #12) RED CAT – Reduction #13) Zn0→ Zn2+ + 2e- #14) 3Zn0 + 2Cr3+→ 3Zn2+ + 2Cr0

  6. #15 ELECTROLYSIS 1e- Ag0 Ag1+ 1e- D.C. SOURCE (BATTERY) 1e- 1e- The fork to be electroplated + Ag Ag1+ - - - + - - THE ANODE IS SOLID SILVER, THE SOURCE OF SILVER IN THIS REACTION. Ag0 + • The fork is the cathode because: (A) • It is the negative electrode in electroplating • It is the site where the silver ions are reduced to make a layer of solid silver (Ag+1 + 1e- →Ag0)

  7. #17 & 18 Zinc/Copper Cell 2e- 2e- VOLTMETER 2e- 2e- Na+ SO42- Na+ SO42- SO42- Na+ Na+ 2e- Zn Zn Cu 2e- - Zn2+ #17) B A→F →E →D #18) D Ions move through salt bridge Cu2+ Cu Na+ Na+ SO42- + - Cu2+ Cu + - - SO42- + Zn0(s) 2e- + Zn2+ 2e- + Cu2+ Cu0(s) ANODE (ANOX) CATHODE (REDCAT)

  8. (D) electrolytic cells use an applied energy source. • Electrons flow from anode to cathode, identify which metal is oxidized using Table J. • The function of the salt bridge is to transfer ions and maintain charge. • Zn0 → Zn2+ + 2e- • (A) cathode at B • Cl- ion will be attracted to the positive electrode and oxidized there. • Zn0 + 2Ag+→ Zn+2 + 2Ag0 (D) The concentration of Zn+2 increases.