Page 128 - The Ontario Curriculum, Grades 11 and 12: Science, 2008 (revised)

Grade 12, College Preparation
d1. analyse technological applications or processes relating to oxidation-reduction reactions, and assess their impact on the environment;
d2. investigate the oxidation-reduction reaction that occurs in a galvanic cell;
d3. demonstrate an understanding of the concepts of oxidation and reduction, and the principles of oxidation-reduction reactions.
D1. Relating Science to Technology, Society, and the Environment
D2. Developing Skills of Investigation and Communication
d. electrochemiStry OVERALL EXPECTATIONS
By the end of this course, students will:
THE ONTARIO CURRICULUM, GRADES 11 AND 12 | science
SPECIFIC EXPECTATIONS
By the end of this course, students will:
d1.1 analyse, on the basis of research, a techno- logical application that is based on the oxidation-reduction (redox) reaction that occurs in galvanic cells (e.g., in cardiac pacemakers, batteries, electroplating) [IP, PR, AI, C]
Sample issue: Hydrogen fuel cells use a redox reaction that produces water, rather than environmentally harmful greenhouse gases,
as waste. Although some cars could run on fuel cells, practical problems, such as the storage and cost of producing hydrogen, currently limit the usefulness of this technology in the transportation sector.
Sample questions: What chemical reactions occur in rechargeable and non-rechargeable batteries? How do different technologies use different types of galvanic cells for their energy? How does the redox reaction occur in the electroplating process? Why is this reaction necessary?
d1.2 analyse, on the basis of research, the causes of metal corrosion, and assess the environmental impact of some techniques used to protect metals from corrosion (e.g., rustproofing, painting, cathodic protection, galvanization) [IP, PR, AI, C]
Sample issue: The maintenance of large span- bridges over salt water has always been challenging, because the salt water spray causes corrosion. Newer bridges use support structures
that have been protected from corrosion, but long-term studies have not been done on the impact of these methods on the environment.
Sample questions: What are some of the tech- niques used to protect metals from corrosion? What are the benefits and risks to the environ- ment of the electroplating of metals? Why do metal orthodontic braces not corrode?
By the end of this course, students will:
d2.1 use appropriate terminology related to electrochemistry, including, but not limited to: oxidation, anode, and electrolyte [C]
d2.2 build a galvanic cell and measure its voltage [PR, AI]
d2.3 analyse the processes in galvanic cells, and draw labelled diagrams of these cells to show the oxidation or reduction reaction that occurs in each of the half-cells, the direction of electron flow, the location of the electrodes, and the dir- ection of ion movement [AI, C]
d2.4 design and conduct an inquiry to determine the factors that affect rate of corrosion of a metal (e.g., stress on the metal, contact between two metals, surface oxide, the nature of the electrolyte, the nature of the metal) [IP, PR, AI]
12