10/20/11

Post date: Oct 24, 2011 1:16:38 AM

    • Bell Ringer (verbal): What is the formula for the compound formed by Magnesium and Chlorine?

    • Faster way to write a formula:

      1. Look up the valence numbers of each element involved

      2. Decide how many electrons each element will want to give away or take to get a full outer layer. We'll call this number of the electrons the "move number"

      3. Write the symbols of each element together. The subscripts for the formula are the "move numbers", but are switched

    • Example: Magnesium and Chlorine

      • Magnesium has a valence number of 2, Chlorine of 7

      • Magnesium will give away 2, Chlorine will take 1

      • The formula is MgCl2 (the 2 from magnesium goes to chlorine, the 1 from chlorine goes to magnesium)

    • Naming ionic compounds

      • Write the formula of each element together (left-most element on periodic table is also on the left in the name and formula)

      • Change the ending of the 2nd element to "ide"

      • Example: MgCl2 would be named Magnesium chloride

    • Fast ionic bonding assignment - for each of the following combinations of elements, write the formula using this faster method AND write the name of the compound

      1. Sodium and Sulfur

      2. Magnesium and Nitrogen

      3. Magnesium and Carbon

      4. Potassium and Sulfur

      5. Calcium and Bromine