AP Chemistry Suggested Summer Work

Transcription

1 AP Chemistry Suggested Summer Work AP Chemistry is a difficult course. It is not all about memorization, but there are some things you simply must memorize. It is essential for success in learning the concepts covered in this course. It is to your advantage to memorize the material in this packet well before the first day of school and review it often. As I am sure you know, true learning (and retention) will come only from reviewing material regularly, as opposed to cramming. You will be quizzed on this material within the first week of the school year, so plan ahead in order to be successful! Make flashcards, have friends and family quiz you, take this packet with you on vacation, or do whatever else it takes to get this information firmly planted in your head! Spending a mere five to ten minutes each day looking this over will be far more effective in the long run than attempting to cram the night before the quiz. DO NOT PROCRASTINATE!!! For those who really want to get ahead, you can also start reading and outlining the first three chapters from Chemistry (Chang), 9 th edition once you receive your textbook. The topics of memorization are listed below, and the details are covered throughout this packet. Also, you may find much of this material outlined in your Honors Chemistry note packets. If you still have them lying around somewhere dig them out and look them over. They will also be a valuable reference tool throughout the year. 1. Polyatomic ions (name, charge, symbol) 2. Variable valences (charges) and colors for transition metals 3. Rules for naming ionic compounds 4. Rules for naming acids, and the seven strong acids 5. Solubility rules 6. Rules for determining oxidation numbers

2 Solubility Rules 1. All compounds containing alkali metal cations and the ammonium ion are soluble. 2. All compounds containing NO 3, ClO 4, ClO 3, HCO 3 and C 2 H 3 O 2 anions are soluble. 3. All chlorides, bromides and iodides are soluble EXCEPT those containing Ag +, Pb 2+, or Hg All sulfates are soluble EXCEPT those containing Ag +, Pb 2+, Hg 2+, Sr 2+, Ca 2+, or Ba All hydroxides are insoluble EXCEPT compounds of the alkali metals, NH 4 +, Sr 2+, or Ba 2+. Ca 2+ is temperature dependent. 6. All compounds containing PO 4 3, S 2, CO 3 2 and SO 3 2 ions are insoluble EXCEPT compounds of the alkali metals or NH 4 +. These are generalizations. We will learn later in the year that many compounds are slightly soluble, which will complicate things slightly. However, memorizing these generalizations now is essential for topics covered early in the year, and it will make our study of solubility later in the year easier. Rules for determining Oxidation Number Oxidation Number: A number assigned to an atom in a molecular compound or molecular ion that indicates the distribution of electrons among the bonded atoms. 1. In free elements (including diatomic ones) each atom has an oxidation number of zero. 2. For monatomic ions the oxidation number is equal to the charge of the ion. 3. The more electronegative element in a binary compound is assigned the number equal to the charge it would have if it were an ion. 4. Fluorine has an oxidation number of 1 in ALL of its compounds. Other halogens have negative oxidation numbers when they occur as halide ions in their compounds, but when combined with oxygen they have positive oxidation numbers. 5. The oxidation number of oxygen is 2 unless it is combined with fluorine (when it is +2) or in peroxides (when it is 1). 6. The oxidation number of hydrogen is +1 except when bonded to metals in binary compounds. In such cases its oxidation number is In compounds, the elements of groups one and two as well as aluminum have oxidation numbers of +1, +2, and respectively. 8. In a neutral molecule the sum of all the oxidation numbers must be zero. 9. In a polyatomic ion the sum of all of the oxidation numbers in the ion must equal the net charge of the ion. 10. Oxidation numbers do not have to be integers, though they typically are. (Ex: In O 2 each O has an oxidation number of 1/2.)

3 Polyatomic Ions NAME SYMBOL AND CHARGE ammonium + NH 4 acetate (or ethanoate) C 2 H 3 O 2 (CH 3 COO ) bromate BrO 3 chlorate ClO 3 chlorite ClO 2 cyanide CN dihydrogen phosphate H 2 PO 4 hypochlorite ClO hydrogen carbonate (or bicarbonate) HCO 3 hydrogen sulfate (or bisulfate) HSO 4 hydrogen sulfite (or bisulfite) HSO 3 hydroxide OH iodate IO 3 nitrate NO 3 nitrite NO 2 perchlorate ClO 4 permanganate MnO 4 thiocyanate SCN carbonate 2 CO 3 chromate 2 CrO 4 dichromate 2 Cr 2 O 7 oxalate 2 C 2 O 4 selenate 2 SeO 4 silicate 2 SiO 3 sulfate 2 SO 4 sulfite 2 SO 3 phosphate PO 4 3 Rules for Naming Ionic Compounds 1. Name the cation. 2. Name the anion. root of nonmetal plus ide suffix ending if the compound is binary polyatomic ion s name if applicable do not change ending Examples: CaCl 2 = calcium chloride FeCl 3 = iron (III) chloride Al 2 (SO 4 ) 3 = aluminum sulfate CuSO 4 = copper (II) sulfate NH 4 OH = ammonium hydroxide

4 Variable Valences for Transition Metals Name Symbol Charge Stock Name Chromium Cr +2 Chromium (II) Chromium (III) Manganese Mn +2 Manganese (II) Manganese (III) Iron Fe +2 Iron (II) Iron (III) Cobalt Co +2 Cobalt (II) Cobalt (III) Copper Cu Copper (I) Copper (II) Lead Pb Lead (II) Lead (IV) Mercury Hg Mercury (I) Mercury (II) Tin Sn Tin (II) Tin (IV) Gold Au +1 Gold (I) Gold (III) Silver Ag (rare) Silver (I) Silver (II) Bismuth Bi +5 Bismuth (III) Bismuth (V) Antimony Sb +5 Antimony (III) Antimony (V) Cadmium Cd +2 Cadmium Zinc Zn +2 Zinc Common Ion Colors in Aqueous Solution Ion Color Ion Color Cu 2+ Bluegreen Fe 2+ Light bluegreen Cr 2+ Blue Fe 3+ Yellowbrown Co 2+ Pink Ni 2+ Green Mn 2+ Faint pink 2 CrO 4 Yellow MnO 4 Dark purple 2 Cr 2 O 7 Orange

5 Rules for Naming an Acid 1. When the name of the anion ends in ide, the acid name begins with the prefix hydroand the stem of the anion has the suffix ic. This is followed by the word acid. Pattern: hydro ic acid Examples: HCl = hydrochloric acid HCN = hydrocyanic acid 2. When the name of the anion ends in ite, the acid name is the stem of the anion with the suffix ous. This is followed by the word acid. Pattern: ous acid Example: HNO 2 = nitrous acid 3. When the name of the anion ends in ate, the acid name is the stem of the anion with the suffix ic. This is followed by the word acid. Pattern: ic acid Example: HNO 3 = nitric acid Strong Acids Hydrochloric acid Hydrobromic acid Hydroiodic acid Perchloric acid Chloric acid Nitric acid Sulfuric acid

6 In addition to studying for your first quiz you have the opportunity to earn some extra credit over the summer! Here is what to do: 1. Order / purchase your own copy of, AP Achiever Advanced Placement Exam Prep Guide, for Chemistry, McGraw Hill, 2007 or newer. (I refer to the 2007 edition, as that is what I personally own. If you have a newer edition, some page numbers may be slightly different. Please use your logic and reasoning to adjust as needed.) a. This book was written specifically to supplement the Chang text used in class, which is why it was chosen over other test prep books. Sadly, like most, it does contain a typo here and there. Overall, though, I am quite satisfied with it. b. If it is difficult to find in stores, it is available at (Barnes & Noble) and other online retailers. Order early!!! 2. Read the introductory material on pages vi xv. Highlight material that applies to you. 3. Use the AP Chem Exam I Multiple Choice (starting on p. 395) as a diagnostic exam. Attempt the entire test, though there may be some topics that are unfamiliar to you. The purpose is to determine what you know from previous courses and what is new or forgotten. You can write in the book or on separate paper. I suggest writing on separate paper so that you can retake this test at the end of the course. 4. Read and study the first three chapters: a. Chemistry: The Study of Change b. Atoms, Molecules, and Ions c. Mass Relationships in Chemical Reactions Highlight, take notes, and complete all review questions at the end of each chapter. Completing this over the summer will give you an edge when it comes to our first unit (chapters one through three) of study in the fall. 5. Bring your highlighted book with any supplemental notes/problems that are on separate paper to class on the first day of school in August. Bonus points will be assigned to you and then the book will be returned. As we go through the year you should continue to use your test prep book to help you through difficult chapters in your Chang text. Thus, you should find that this investment pays off throughout the entire course. Personal Message While this part of the summer assignment is optional, words cannot express how strongly I encourage it. Every year it seems that there is one person who does not take advantage of this opportunity, and that person is often trailing behind the rest of the class throughout the year. Doing this over the summer will set you on the right track not only for the first unit, but for the entire year. In addition, this year I had two students who maintained over 100% right up to the end of the first semester thanks to the extra credit earned on this summer assignment, along with high grades earned throughout the semester. While I will offer opportunities for extra credit second semester as well, this will be the only opportunity during first semester. Please take advantage of it while it is available.