Monday, October 4, 2010

Bonding and Naming

Sorry to not be posting, I have been busy teaching bonding and naming. There are two basic types of bonds and each requires a separate set of rules. I taught one then the other and students got it perfectly. However, when you mix them together and they have to decide which method to use, it somehow gets mixed up.

If it is a + and -, the bond is ionic. The electrons are given and taken in the bond. To get the formula, you criss cross the charges. To name it, you say the name of the metal, then the name of the nonmetal with an -ide ending. If it is a metal from DForP block, then you use a roman numeral to indicate the charge of the metal.

If it is a - and -, the bond is covalent. The electrons are shared in the bond. To get the formula, you have to draw the Lewis Dot structures for the elements and connect the dots that don't have friends. You write the formula based on your drawing. To name it, use prefixes to indicate the number of atoms in the formula and the second one ends in -ide. For these it doesn't matter which element comes first.

The test on this material is today. Tonight's homework is to finish the watermelon sheet.

1 comment:

Anonymous said...

Hi Ms.J. I am a first year high school biology, chemistry, physics, and physical science teacher in Baton Rouge. I stumbled upon your blog looking for pictures of plankton and I love it! Could you tell me where I can find the foldable for the history of the atom (dalton, rutherford,...)? Also, do you have any instructions for playing Guess Who with the elements?
As a first year teacher I would really appreciate the help!! My email is cwarfel@thebrightonschool.org