When Done Test Pg. 324 #1-9 Pg. 325 #1-5 Pg. 325 #1-4
The Nature of Oxidation- Reduction Reactions I will be able to explain how oxidation and reduction reactions involve the transfer of electrons. I will be able to write half-reactions.
Oxidation and Reduction Loss of electrons = oxidation Gain of electrons = reduction These 2 reactions happen at the same time because 1 element loses electrons to the one who gains them.
Oxidation and Reduction These 2 reactions happen at the same time because 1 element loses electrons to the one who gains them.
Single Displacement Reactions are Redox Reactions
Writing Half Reactions A piece of copper wire is placed in a silver nitrate solution: a) Write the ionic equation b) Write the net ionic equation c) Write the oxidation half reaction d) Write the reduction half reaction
Writing Half Reactions A piece of aluminum wire is placed in a copper(ii)sulfate solution: a) Write the ionic equation b) Write the net ionic equation c) Write the oxidation half reaction d) Write the reduction half reaction
Today s Tasks Pg. 326 #1-3 Pg. 328 #4-6 Worksheet Pg. 1
Oxidation Numbers I will be able to assign oxidation numbers.
What is an oxidation number? It is a number that is assigned to an individual atom or ion in a substance using a set of rules. Pg. 329
Assigning Oxidation numbers CaO HNO 3
Easiest way to figure out if a reaction is a redox reaction or not assign oxidation numbers! Which of the following are redox reactions? Explain how you know, if it is redox make reference to # elections transferred. a) ZnO + Al 2 S 3 ZnS + Al 2 O 3
Easiest way to figure out if a reaction is a redox reaction or not assign oxidation numbers! Which of the following are redox reactions? Explain how you know, if it is redox make reference to # elections transferred. b) Zn + O 2 ZnO
Easiest way to figure out if a reaction is a redox reaction or not assign oxidation numbers! Which of the following are redox reactions? Explain how you know, if it is redox make reference to # elections transferred. c) Cu + AgNO 3 Ag + Cu(NO 3 ) 2
Oxidizing & Reducing Agents Oxidizing agent: a reactant that oxidizes another reactant by accepting electrons (i.e. the reactant that is reduced). Reducing agent: a reactant that reduces another by donating electrons (i.e. the reactant that is oxidized)
Today s Tasks Pg. 330 #7-8 Pg. 331 #9-11 Worksheet Pg. 2 & 3 Worksheet
Redox Reactions & Corrosion I will be able to explain why corrosion is a redox reaction
Today s Tasks: Read Pgs. 333-335 Define corrosion Explain the rusting process and how it is a form of corrosion. There are several ways to slow down or prevent corrosion. Explain how the following help: Surface metal oxides Galvanization Sacrificial Metals Read Pg. 336 Explain how salt promotes rusting. Pg. 337 #1-10
Galvanic Cells: Using Redox Reactions to make electricity! I will be able to explain how galvanic cells work.
Why is this unit called electrochemistry? Because we use chemistry to make electricity! A galvanic cell is a device that uses oxidation-reduction reactions to produce electrical energy. i.e. a battery uses redox reactions to make a flow of electrons that we use to power devices.
A deeper look at Galvanic Cells It has many parts: The cathode the electrode where reduction occurs. The anode the electrode where the oxidation occurs. The salt bridge allows a current to flow between the separate parts of an electrochemical cell. The solutions are the reducing and oxidizing agents and separate the two reactions. Electrons flow from the anode to the cathode.
Identifying the Anode and Cathode It is based on the activity series we looked at in unit 1. The metal higher up will be the anode and the metal that is lower will be the cathode.
In each pair identify the anode and cathode Au / Zn Ca / Mg
The diagram below represents a galvanic cell with electrodes made of potassium and lead. Match the labels in the diagram with the descriptions in the table that follows. Label Description potassium metal an electrode called the anode salt bridge lead metal solution of Pb(NO 3 ) 2 (aq) an electrode called the cathode solution of KNO 3 (aq)
Today s Tasks Pg. 350 #1-3 Pg. 353 #4-7 Pg. 354 #2a Worksheet Pg. 4 Prepare for open notebook test