Journal 9/30/14

1. Journal 9/30/14 Do you think God designed the world so we can find every combination of elements? Why or why not? Objective Tonight’s Homework To learn about a special set of ions practice with polyatomic ions

2. Polyatomic Ions Today we’re going to add something to our naming foldable called “polyatomic ions”. A polyatomic ion is a special group of atoms that bond together. But unlike other compounds, polyatomic ions don’t balance out their + and – in the end. Example: NO2- O N O Normally, this grouping should only have 17 electrons. But 17 electrons doesn’t give each atom 8. Instead, this group has an extra electron. So with 18 electrons, everything works, but it has an overall minus. • • • • • • • • • • • • • • • • • •

3. Polyatomic Ions Today’s addition to your naming foldable should cover 2 pages, just like last time’s.

4. Chemistry Naming Foldable Polyatomic Ions Each polyatomic ion has a specific name. These are always the second thing named when combined with something else. See the list on the opposite page for how to name a polyatomic ion. Example: Pb3(PO4)2 lead phosphate Example: Al(NO3)3 aluminum nitrate Example: Hg(CN)2 mercury cyanide Example: Cu(ClO4)2 copper perchlorate Diatomic Elements If left alone, the elements on the facing page will combine with themselves:

5. Chemistry Naming Foldable

6. Practice with Polyatomic Ions Name each of the following compounds Sr(NO3)2 H2C2O4 CaC2O4 HgF2 Pb(CN)2 NaNO3 K2SO4 Fe(NO3)3 NH4CH3COO

7. Exit Question #19 What is the charge on the polyatomic ion “phosphate”? a) +1 b) 0 c) -1 d) -2 e) -3 f) None of the above