Electrochemistry Lesson 1 Introduction Electrochemistry Is the study

  • Slides: 22
Download presentation
Electrochemistry Lesson 1 Introduction

Electrochemistry Lesson 1 Introduction

Electrochemistry Is the study of reactions that gain or lose electrons.

Electrochemistry Is the study of reactions that gain or lose electrons.

Electrochemistry Is the study of reactions that gain or lose electrons. In this unit

Electrochemistry Is the study of reactions that gain or lose electrons. In this unit we will study:

Battery Reactions- oxidation and reduction

Battery Reactions- oxidation and reduction

Corrosion- oxidation

Corrosion- oxidation

Preventing Corrosion

Preventing Corrosion

Oxidation

Oxidation

Electroplating- reduction

Electroplating- reduction

Refining Metals- reduction

Refining Metals- reduction

Oxidation means loss of electrons LEO Loss. Electrons. Oxidation Half Reactions show Metals or

Oxidation means loss of electrons LEO Loss. Electrons. Oxidation Half Reactions show Metals or Anions lose electrons 0 Na metal +1 → Na+ + 1 e- ion Oxidation- electrons are on the right Balance charge Add electron to most positive side

Oxidation means loss of electrons LEO Loss. Electrons. Oxidation Half Reactions show Metals or

Oxidation means loss of electrons LEO Loss. Electrons. Oxidation Half Reactions show Metals or Anions lose electrons 0 Al metal +3 → Al 3+ + 3 e- ion Oxidation- electrons are on the right Balance charge Add electrons to most positive side

Oxidation means loss of electrons LEO Loss. Electrons. Oxidation Half Reactions show Metals or

Oxidation means loss of electrons LEO Loss. Electrons. Oxidation Half Reactions show Metals or Anions lose electrons 2 O 2 anion → O 2 + 4 e- atom Oxidation- electrons are on the right Balance for numbers Balance charge Add electrons to most positive side

Reduction means gain of electrons GER Gain. Electrons. Reduction Half Reactions show Nonmetals or

Reduction means gain of electrons GER Gain. Electrons. Reduction Half Reactions show Nonmetals or Cations gain electrons 3+ Ga 3+ cation 0 + 3 e- → Ga atom Reduction- electrons are on the left Balance charge Add electrons to most positive side

Reduction means gain of electrons GER Gain. Electrons. Reduction Half Reactions show Nonmetals or

Reduction means gain of electrons GER Gain. Electrons. Reduction Half Reactions show Nonmetals or Cations gain electrons N 2 + 6 e- → 2 N 3 - Reduction- electrons are on the left

Balance each simple half reaction 1. Ca → Ca 2+ + 2. F 2

Balance each simple half reaction 1. Ca → Ca 2+ + 2. F 2 + 2 e- → 3. O 2 2 e- 2 F- reduction 5. + 4 e- → 2 O 2 Ga 3+ Ga → + 3 e -→ 2 Br Br 2 + 2 e- 6. Li+ 4. + e- → oxidation Li reduction oxidation reduction

Redox Reactions Both oxidation and reduction must occur. The electrons gained equals the electrons

Redox Reactions Both oxidation and reduction must occur. The electrons gained equals the electrons lost. 1. Al 2 ( Al + Zn(NO 3)2 → Al 3+ + 3 ( Zn 2+ + 2 e- 3 e-) → oxidation Zn ) reduction 2 Al + 3 Zn 2+ → 2 Al 3+ + 3 Zn redox

2. Cl 2 + Na Cl 2 + 2 e- → 2 Cl- reduction

2. Cl 2 + Na Cl 2 + 2 e- → 2 Cl- reduction Na+ + 1 e-) oxidation + 2 Na+ redox 2(Na → Cl 2 + 2 Na → 2 Cl-

Oxidizing Agents cause oxidation by undergoing reduction. They gain electrons. Nonmetals and cations are

Oxidizing Agents cause oxidation by undergoing reduction. They gain electrons. Nonmetals and cations are oxidizing agents because they gain electrons. Cl 2 Ca 2+ Cl 2 + Ca 2+ F 2 2 e- Na+ → 2 Cl- Both can gain electrons + 2 e- → Ca

Reducing Agents cause reduction by undergoing oxidation. They lose electrons. Metals and anions are

Reducing Agents cause reduction by undergoing oxidation. They lose electrons. Metals and anions are reducing agents because they lose electrons. N 3 Al O 2 Li Both can lose electrons 2 N 3 Al → N 2 + 6 e- → Al 3+ + 3 e-

You need to be able to tell an oxidizing agent from a reducing agent.

You need to be able to tell an oxidizing agent from a reducing agent. Circle each oxidizing agent. They can reduce or gain electrons Ga Rb+ I- P 4 Fe Co 2+ S I 2 Cu Pb 2+ Li Br-

Label each reactant as an oxidizing or reducing agent. Gaining electrons Losing electrons 2

Label each reactant as an oxidizing or reducing agent. Gaining electrons Losing electrons 2 Ag+ + Pb → Reduction Oxidation Ox Agent Red Agent 2 Ag + Pb 2+

Label each reactant as an oxidizing or reducing agent. Losing electrons Gaining electrons 6

Label each reactant as an oxidizing or reducing agent. Losing electrons Gaining electrons 6 I+ 2 Al 3+ → Oxidation Reduction Red Agent Ox Agent 3 I 2 + 2 Al