Saturday, December 15, 2012

Oxidation-Reduction Reactions






 Elements can lose or gain electrons and become ions.  In a compound, electrons are shared or transferred to another element.  The sum of the charges is zero for a compound.  The oxidation numbers found on the periodic table can be used to follow the exchange of electrons between elements in a compound.
 Use the following search engine to help learn about redox reactions:

 http://www.google.com/cse/home?cx=005536324144386362660:3ubdk9d3kw8
 .

This search engine provides all the information you need to understand Oxidation and Reduction reactions
As you follow the links,  make sure you can do the following:
  • assign oxidation numbers to elements in a compound.
  • know the rules for assigning oxidation numbers
  • Determine which element in a redox reaction is oxidized and which one is reduced.
  • write an oxidation half- reaction and a reduction half-reaction
  • Label the parts of an electrochemical cell
  • trace the path of electrons through a voltaic cell and an electrolytic cell
  • compare an electrolytic cell to a voltaic cell.  How are they similar?  How are they different?
  • In what ways are electrochemical cells useful to us?  How do we use this chemical reaction for our benefit.
You have four days to complete  this assignment.  At the conclusion you will go to the following link and take an online quiz:

https://docs.google.com/spreadsheet/gform?key=0AnQFuibqI5nPdElvOEZkMm95MEc3bXdzZUVQUHJEa0E&hl=en#edit
Enjoy!!


Sunday, November 18, 2012

You too are made of ELEMENTS!

When you think of the study of Chemistry, the first object that comes to mind is an atom.
 What are atoms?

Atoms have a structure.  They have a nucleus surrounded by energy levels. There are 3 subatomic particles: protons, neutrons and electrons








Each subatomic particle has a charge.


Watch this presentation on the "Atoms Family" to get a better understanding of the parts of an atom. 


Enjoy this classic video made by Tom Leher 
The Element Song