Review:
­ roman numerals
­
multivalent ions
­ naming multivalent ions
­
writing formulas for multivalent ions
Sep 21­10:28 AM
Polyatomic Ions
­
polyatomic ions (complex ions) are a group of ions that are covalently bonded which then gain or lose electrons to become stable
­
many of the ingredient labels on products you find in your house have names with these endings
­ sodium phosphate (cleaners)
­ calcium carbonate (antacid tablets)
­ sodium hypochlorite (household bleach)
­ sodium glutamate (meat tenderizer)
Sep 21­10:29 AM
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Writing Chemical Formulas for Compounds with Polyatomic Ions
­ the formula writing procedure follows the same approach used earlier
­ you have to balance the ion charges in order to determine the number of individual ions
NOTE: you will need your chemistry data sheet to complete this section
Sep 21­10:37 AM
STEP 1: When given the name write the chemical formula of the cation first and the anion second
STEP 2: Put brackets around the polyatomic ion (this can be determined by looking at the chemistry data sheet)
STEP 3: Using crossover method balance the charges
STEP 4: Remove brackets if subscript is one
Sep 21­10:40 AM
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Examples:
Write the chemical formula for the following:
a. sodium chlorite
Na + (ClO2­)
= NaClO2
b. iron (III) sulfate
c. ammonium permanganate
Sep 25­7:47 AM
Writing Names for Compounds Containing Polyatomic Ions
Writing names for compounds containing polyatomic ions is as straight forward as the process for naming binary ionic compounds
1. Begin by identifying the anion
2. Then identify the cation
3. Write the compound name: cation first anion second
Sep 25­7:51 AM
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Example:
Write the IUPAC name for each formula:
a. (NH4)3PO4
b. Cr(NO3)3
Sep 25­7:54 AM
Readings:
Pages 196 ­ 198
Activities:
Complete worksheet provided
Sep 25­7:57 AM
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