Ionic Compounds from mono and polyatomic ions

1. Ionic Compounds from mono and polyatomic ions Objective: naming mono-atomic ions and the compounds they form, and poly-atomic ions and the compounds they form. FIRST... sodium forms an ion, so does chlorine. Write the atomic symbol, the ionic symbol, and then see if you can figure out how they combine into a NEUTRAL IONIC COMPOUND. Chlorine is bigger, so chlorine is the pink one in this picture.

2. Forming Ionic Compounds, the rules... The sodium atom forms a cation, the chlorine atom forms an anion. The Na becomes Na+1. The Cl becomes Cl–1. The charges are equal and opposite, so they will be able to combine in a 1:1 ratio, forming neutral NaCl,which is sodium chloride(table salt).

3. NaCl is sodium chloride. • Let’s look at how these names work. • The cation always goes first. • That means the anion has to go second. • That is always true. • The metal is always the cation. You say the name of the metal atom just as it is. • The anion here is chlorine. We’ll have to change that name chlorine to chloride to be proper. • The mono-atomic anions get an -ide name ending. • Thus, NaCl is sodium chloride (not sodium chlorine, or chlorine sodium, etc.)

4. Let’s try to name these four ionic compounds. PLEASE NOTE, the metals are always first, the non-metals are always second. All ionic compounds are made up of a |METAL + NON-METAL KCl - LiBr - MgO - CsS -

5. All ionic compounds are made up of a |METAL + NON-METAL the metal atom name is the exact same as its name as an atom, the anion gets the -ide ending. KCl - potassium chloride LiBr - lithium bromide MgO - magnesium oxide CsS - cesium sulfide MgO forms, just like in lab.

6. THINK All ionic compounds are NEUTRAL- even though they form from charged cations (+) combining with charged anions (-).The positive charges must equal the negative charges. THINK, what if an ionic compound forms between calcium and chlorine? What are the ions, what is the compound called, and what is the chemical formula for this?

7. CALCIUM + CHLORINE Calcium Chloride Calcium atom becomes calcium cation Chlorine atom becomes chlorine anion Ca + Cl yields hey wait a second, the positives don’t equal the negatives! Since calcium is a +2 cation, it would take two -1 anions to form a NEUTRAL IONIC COMPOUND. That’s what happens! Ca+2 + Cl-1 + Cl-1 CaCl2 and that is called calcium chloride, a neutral ionic compound

8. Now try to form these neutral ionically bonded compounds from the following ions... copy this chart into your notes now.

9. Let’s see how well you did, we’ll check the ions first then we’ll finish up on the next slide.

10. And now for the rest of the story. Hang in there, we’re learning SO much today!

11. And now for the rest of the story. Hang in there, we’re learning SO much today!

12. And now you’re smarter than you ever imagined! Time to put you to the test. Get ready, keep your thinking hats on! Here are your atoms, determine how to form proper cations and proper anions, and make NEUTRAL IONIC COMPOUNDS. Make sure your positives always equal your negatives! Good Luck! • aluminum plus oxygen • aluminum plus chlorine • magnesium plus nitrogen • potassium plus calcium

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14. aluminum plus oxygen • aluminum plus chlorine • magnesium plus nitrogen • potassium plus calcium make sure that the positives are equal to the negatives to form NEUTRAL IONIC compounds. The cations come first, the anions second, with the -ide ending names.

15. Chemistry keeps getting more real, here comes some more really great stuff. Take out page one of your reference tables. Check out TABLE E Talk to your neighbor, what’s this table all about? We’re psyched! We learned this stuff from Charlie Arbuiso a long time ago and now we’re studying chemistry in the wild!

16. Poly Atomic Ions Table E lists a bunch of ions that are formed when a few atoms combine together but act as a unit. They are given to you and you will not have to memorize them. Remember where this Table E is though, you’ll need it a lot! POLY means many ATOMIC means about atoms IONS means charged atoms (positive or negative) THEY ACT AS A UNIT, that’s the important part!

17. Let’s combine a few cations and anions from the Periodic Table as well as Table E. The easy part is that there is NO RULE for polyatomic ion naming, they keep the names that they have on the table E. Less thinking = more time for FUN.

18. Let’s see how you did here. compounds first, then next slide for the names Be sure to note that the compounds are ALL NEUTRAL.

19. Let’s see how you did here. compounds first, then next slide for the names Be sure to note that the compounds are ALL NEUTRAL.

20. This is hard stuff. You are smart kids. We will practice this until it’s like tying your shoes or riding a bicycle, or even, like walking around your own house in the dark. It’s hard, you’re new at it, relax. Does your teacher look nervous? No, so you shouldn’t be either.