Unit 1: Chemistry Basics 1.1 Polyatomic Ions

Taking Notes in AP Chem I will give you a print out of the slides. This is exactly how it will go in college. Anything I write, you should write.

For the AP exam…. While they give us a periodic table they do not give us a list of polyatomic ions. We must memorize the name, formula and charge for the common ones PolyatomicName NH 4 + Ammonium NO 2 - Nitrite NO 3 - Nitrate SO 3 2- Sulfite SO 4 2- Sulfate HSO 4 - Hydrogen sulfate (bisulfate) OH - Hydroxide CN - Cyanide OCN - Cyanate SCN - Thiocyanate PO 4 3- Phosphate HPO 4 2- Hydrogen phosphate H 2 PO 4 - Dihydrogen phosphate CO 3 2- Carbonate HCO 3 - Hydrogen carbonate (bicarbonate) ClO - Hypochlorite ClO 2 - Chlorite ClO 3 - Chlorate ClO 4 - Perchlorate BrO - Hypobromite BrO 2 - Bromite BrO 3 - Bromate BrO 4 - Perbromate IO - Hypoiodite IO 2 - Iodite IO 3 - Iodate IO 4 - Periodate C2H3O2-C2H3O2- Acetate MnO 4 - Permanganate Cr 2 O 7 2- Dichromate CrO 4 2- Chromate O 2 2- Peroxide C 2 O 4 2- Oxalate NH 2 - Amide BO 3 3- Borate S 2 O 3 2- Thiosulfate

Here are some resources to help you Tricks for memorizing polyatomics polyatomic-ions-quizhttp:// polyatomic-ions-quiz school/story.php?title=polyatomic-ions_2http:// school/story.php?title=polyatomic-ions_2

Nick the Camel ate a Clam for Supper in Phoenix Count consonants for # of oxygen atoms Count vowels for negative charge of polyatomic This trick only works for the following 5 polyatomic ions that end in ate

Nick the Camel ate a Clam for Supper in Phoenix Nick –3 consonants = –1 vowel = Hi I’m Nick

Nick the Camel ate a Clam for Supper in Phoenix Camel –3 consonants = –2 vowel =

Nick the Camel ate a Clam for Supper in Phoenix Clam –3 consonants = –1 vowel =

Nick the Camel ate a Clam for Supper in Phoenix Supper –4 consonants = –2 vowels =

Nick the Camel ate a Clam for Supper in Phoenix Phoenix –4 consonants = –3 vowels =

Other helpful hints… There are only 2 polyatomic ions that we need to memorize that have 3 - charge –Phosphate PO 4 3- –Borate BO 3 3- We can use “nick the camel” to get phosphate If we look at PT you know boron

Halogens group (column) #7A for 1 - ions Polyatomic Ions that start with Cl Br I All make 1 - polyatomic ions

…. Combining rules for halogens Polyatomic Ions that start with Cl, Br, I All make 1 - polyatomic ions And if “ate” is the base All of these have 3 oxygens in “ate” form ClO 3 - = chlorate BrO 3 - = bromate I O 3 - = iodate

normal Think of “ate” for as the “normal poly form ” So if it changes to “ite” – that means one less oxygen but no charge change SO 4 2- sulfate SO 3 2- sulfite

“ Hypo” prefix means one less …so one less oxygen and no charge change “Per” prefix mean one more…so one more oxygen and no charge change ClO - ClO 2 - ClO 3 - ClO 4 - chlorate

Hydrogen in the name Means literally they added one hydrogen atom Since hydrogen ions are often 1 + charge So.. The overall charge must change by adding 1 + CO 3 2- HCO 3 - I** old naming system instead of hydrogen they added prefix ”bi” to indicate one hydrogen atom was added bicarbonate HCO 3 -

Dihydrogen Means literally they added two hydrogen atom Since hydrogen ions are often 1 + charge So.. The overall charge must change by adding = 2 + PO 4 3- HPO 4 2- H 2 PO 4 - ** note this only can happen if “base” is 3 - charge This is the only dihydrogen one you need to know

Thio… Thio = means take away one Oxygen and replace it with one Sulfur and don’t change the charge Sulfate = Thiosulfate = Cyanate = Thiocyanate =

That leaves 10 more out of the 36 on the list Ammonium Hydroxide Cyanide Acetate Permanganate Dichromate Chromate Peroxide Oxalate Amide