Stuff to KNOW. AP Chemistry, Fall 2018 North Cobb High School. Get excited (and ready) for AP Chemistry!

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1 Get excited (and ready) for AP Chemistry! Included in this packet is information about the exam & registering for it and information you should KNOW (memorize or be able to derive from the wonderful periodic table) or know how to CALCULATE. FYI the PERIOIC TABLE on the AP exam has NO NAMES given, only symbols. We will start class in August with the expectation that you are competent with ALL of this material. There will be a test the first week of class comparable to a Honors Chemistry Final exam. Be ready for it. The attached reviews will help you. If you need help, come see me. Don t freak out about this packet. You probably know more than you think. The answer keys will be available in my classroom the first day of school for you to check your work as you go. If you need more practice in a certain area, let me know. Work all of the problems in a section, (ESPECIALLY: the last set of calculations stoichiometry). If you need help, let me know. Drop by room 716 or me at nena.tippens@cobbk12.org ***Sign up for AP Chem class REMIND: to the number The 2018 AP Chemistry Exam will be Thursday, May 9 at 8:00a! Register for the exam at FYI: The AP Chemistry exam is given at the same time as AP Spanish Literature and Culture. Yes, you can take both classes & both exams. You will take an alternate exam (different than the one given on May 9) on a different date as decided by the College Board. Stuff to KNOW 1. SI base units and prefixes 2. Rules for significant figures 3. Element Names & Symbols (Element symbols 1 to 38 and Ag, Cd, I, Xe, Cs, Ba, W, Hg, Pb, Sn, Rn, Fr, U, Th, Pu, and Am written correctly careful with capital letters Co, not CO! 4. Monatomic Ions a. Ions with (usually) one oxidation state (and how to use the Periodic Table to determine charge): Li +, Na +, K +, Mg 2+, Ca 2+, Sr 2+, Ba 2+, Ag +, Zn 2+, Cd 2+, Al 3+ N 3, O, S, F, Cl, Br, I b. Ions with more than one oxidation state: Cu + Copper (I) or cuprous ion Mn 2+ Manganese (II) or manganous ion Cu 2+ Copper (II) or cupric ion Mn 3+ Manganese (III) or manganic 2+ Hg 2 Mercury (I) or mercurous ion Co 2+ Cobalt (II) or cobaltous ion Hg 2+ Mercury (II) or mercuric ion Co 3+ Cobalt (III) or cobaltic ion Fe 2+ Iron (II) or ferrous ion Sn 2+ Tin (II) or stannous ion Fe 3+ Iron (III) or ferric ion Sn 4+ Tin (IV) or stannic ion Cr 2+ Chromium (II) or chromous ion Pb 2+ Lead (II) or plumbous ion Cr 3+ Chromium (III) or chromic ion Pb 4+ Lead (IV) or plumbic ion

2 5. Strong Acids (for all practical purposes, all others are weak acids): HCl, HBr, HI, H 2 SO 4, HNO 3, HClO 3, HClO 4 6. Strong Bases (for all practical purposes all others are weak): Group I hydroxides and Group II hydroxides (except Be(OH) 2 and Mg(OH) 2 ) 7. Rules for assigning (determining) oxidation numbers: Rule 1: Atoms in a pure element have an oxidation number of zero. Rule 2: The more electronegative element in a binary compound is assigned the number equal to the negative charge it would have as an anion. The lesselectronegative atom is assigned the number equal to the positive charge it would have as a cation. Rule 3: Fluorine has an oxidation number of 1 in all of its compounds because it is the most electronegative element. Rule 4: Oxygen has an oxidation number of 2 in almost all compounds. Exceptions: Peroxides, such as H2O2, in which its oxidation # is 1 When oxygen is in compounds with halogens, such as OF2, its oxidation # is +2. Rule 5: Hydrogen has an oxidation # of +1 in all compounds that are more electronegative than it; it has an oxidation # of 1 in compounds with reactive metals (hydrides). Rule 6: The algebraic sum of the oxidation numbers of all atoms in a neutral compound is zero. Rule 7: The algebraic sum of the oxidation numbers of all atoms in a polyatomic ion is equal to the charge of the ion. Rule 8: Rules 17 apply to covalently bonded atoms; however, oxidation numbers can also be assigned to atoms in ionic compounds. 8. Polyatomic Ions (most you learned in Honors Chemistry) C 2 H 3 O 2 acetate SO 4 sulfate 3 PO 4 phosphate NO 3 nitrate SO 3 sulfite 3 AsO 4 arsenate NO 2 nitrite CO 3 carbonate 3 AsO 3 arsenite CN cyanide C 2 O 4 oxalate OCN cyanate CrO 4 chromate SCN thiocyanate Cr 2 O 7 dichromate MnO 4 permanganate S 2 O 3 thiosulfate OH hydroxide O 2 peroxide HSO 4 bisulfate SeO 4 selenate HCO 3 bicarbonate HPO 4 hydrogen phosphate +1 O 2 superoxide + NH 4 ammonium H 2 PO 4 dihydrogen phosphate ClO 4 perchlorate * ClO 3 chlorate * ClO 2 chlorite * ClO hypochlorite * Br, I and F may be substituted

3 9. Colors of common ions in aqueous solution most common ions are colorless in solution, however, some have distinctive colors. These colors have appeared on past AP Chemistry exams: Fe 2+ and Fe 3+ various colors Cu 2+ blue to green Cr 2+ blue Cr 3+ green or violet Mn 2+ faint pink Ni 2+ green Co 2+ pink MnO 4 dark purple CrO 4 yellow Cr 2 O 7 orange 10. Solubility Rules Soluble Ionic Compounds Exceptions Group IA and ammonium (NH 4+ ) salts none nitrates (NO 3 ) and acetates (C 2 H 3 O ) none Chlorides (Cl ), bromides (Br ) and iodides (I ) Compounds of Ag +, Hg 2 2+, and Pb 2+ Sulfates (SO 4 ) Compounds of Sr 2+, Ba 2+, Ca 2+, and Pb 2+ Sulfides (S ) Insoluble Ionic Compounds Exceptions Compounds of NH 4+, Group IA ions, or Ca 2+, Sr 2+, and Ba 2+ Carbonates (CO 3 ) Compounds of NH 4 + and Group IA ions Phosphates (PO 4 3 ) Hydroxides (OH ) Compounds of NH 4 + and Group IA ions Compounds of NH 4+, Group IA ions, or Ca 2+, Sr 2+, and Ba 2+

4 11. Patterns of Reactions a. Metallic carbonates when heated decompose into metallic oxides and CO 2 (g) Ex: CaCO3(s) CaO(s) + CO2(g) b. Most metallic hydroxides, when heated, decompose into metallic oxides and water. Ex: Ca(OH)2(s) CaO(s) + H2O(g) c. Metallic chlorates, when heated, decompose into metallic chlorides and oxygen. Ex: 2KClO3(s) 2KCl(s) + 3O2(g) d. Some acids, when heated, decompose into nonmetallic oxides and water. Ex: H2SO4 H2O(l) + SO3(g) e. Some oxides, when heated, decompose. Ex: 2HgO(s) 2Hg(l) + O2(g) f. Some decomposition reactions are produced by electricity. Ex: 2H2O(l) 2H2(g) + O2(g) g. Metal + oxygen metal oxide Ex: 2Mg(s) + O2(g) 2MgO(s) h. Nonmetal + oxygen nonmetallic oxide Ex: C(s) + O2(g) CO2(g) i. Metal oxide + water metallic hydroxide Ex: MgO(s) + H2O(l) Mg(OH)2(s) j. Nonmetallic oxide + water acid Ex: CO2(g) + H2O(l) ; H2CO3(aq) k. Metal + nonmetal salt Ex: 2 Na(s) + Cl2(g) 2NaCl(s) l. A few nonmetals combine with each other Ex: 2P(s) + 3Cl2(g) 2PCl3(g) Stuff to know how to CALCULATE (with proper significant figures) 1. Use dimensional analysis method to convert the following: a. 3 meters into centimeters b. 15,050 milligrams into grams c. 3,264 milliliters into liters d. 9,674,444 grams into kilograms 2. Classify each of the following as units of mass, volume, length, density, energy, or pressure a. mg e. kg/m 3 b. ml f. kj c. cm 3 g. atm d. mm h. cal 3. How many significant figures are in each of the following? a mm e. 100 b kj f c x1023 atoms g d L

5 4. Record the following in correct scientific notation: a. 350,000,000 cal b mol c Ǻ d. 765,400,000,000 atoms 5. Calculate the following to the correct number of significant figures. a g / cm3 d x 120 b g / 1.01 L e c. 2.1 x Calculate the mass of a sample of copper that occupies 4.2x10 3 cm 3 if the density of copper is 8.94g/cm Fill in the following table: 8. Element 9. Complete 10. # 11. # neutrons 12. # or ion Symbol protons electrons 13. Fe K O Pb Find the average atomic mass of an element if, out of 100 atoms, 5 have a mass of 176amu, 19 have a mass of 177amu, 27 have a mass of 178amu, 14 have a mass of 179amu and 35 have a mass of 180amu. 39. Strontium consists of four isotopes with masses and percent abundances as follows: amu (0.5%), amu (9.9%), amu (7.0%), and amu (82.6%). Calculate the atomic mass of strontium. 40. Write the complete & Noble gas (abbreviated) ground state electron configurations: a. Strontium b. Iron c. Sulfur d. neodymium 41. Write formulas for the following substances: a. Barium sulfate b. Ammonium chloride c. Chlorine monoxide d. Silicone tetrachloride e. Magnesium fluoride f. Sodium oxide g. Sodium peroxide h. Copper (I) iodide i. Zinc sulfide j. Hydrobromic acid k. Lead (II) acetate l. Sodium permanganate m. Lithium oxalate n. Potassium cyanide o. Iron (III) hydroxide p. Silicone dioxide

6 q. Nitrogen trifluoride r. Chromium (III) oxide s. Cobalt (III) nitrate t. Nitrous acid 42. Name each of the following compounds (Give acid names where appropriate) a. CuSO 4 b. PCl 3 c. N 2 F 4 d. KClO 4 e. (NH 4 ) 2 Cr 2 O 7 f. HNO 2 g. Sr 3 P 2 h. Mg(OH) 2 i. Al 2 S 3 j. AgBr k. P 4 O 10 l. HC 2 H 3 O 2 m. FeI 3 n. Cu 3 PO 4 o. Cs 3 N p. HF 43. Find the mass percent (percent composition) of nitrogen in each of the following compounds: a. NO b. NO 2 c. N 2 O Complete the Following Table: Name of Acid Formula of Acid Name of Anion a. hydrochloric b. HCl c. chloride d. sulfuric acid e. H 2 SO 4 f. sulfate g. h. HC 2 H 3 O 2 or CH 3 COOH 45. Predict the products of the following reactions, write a balanced chemical equation, include states of matters and identify the reaction type. a. sodium carbonate (heated) b. electrolysis of aluminum oxide c. magnesium burned in oxygen d. Ammonium sulfate reacts with barium nitrate. e. Zinc metal is added to a solution of copper (II) chloride. f. Propane gas (C 3 H 8 ) is burned in excess oxygen. g. Solid calcium chlorate is heated strongly. h. Solutions of lead nitrate and calcium iodide are combined. i. Sulfuric acid is combined with sodium hydroxide. i.

7 j. Iron metal shavings are added to hydrochloric acid. k. Sodium metal is added to distilled water. 46. Benzene contains only carbon and hydrogen and has a molar mass of 78.1 g/mol. Analysis shows the compound to be 7.74 % hydrogen by mass. Find the empirical and molecular formulas of benzene. 47. Calcium carbonate decomposes upon heating, producing calcium oxide and carbon dioxide. a. Write a balanced chemical equation for this reaction. b. How many grams of calcium oxide will be produced after grams of calcium carbonate are completely decomposed? c. What is the volume of carbon dioxide gas produced grams of calcium carbonate at STP? 48. Hydrogen gas and bromine gas react to form hydrogen bromide gas. a. Write a balanced equation for this reaction. b. 3.2 grams of hydrogen react with 9.5 grams of bromine. Which is the limiting reagent? c. How many grams of hydrogen bromide gas can be produced using the amounts in (b)? d. How many grams of excess reactant are left unreacted? e. What volume of HBr, measured at STP is produced in (b)? 19. When ammonia gas, oxygen gas and methane gas (CH4) are combined, the products are hydrogen cyanide gas and water. a. Write a balanced chemical equation for this reaction. b. Calculate the mass of each product produced when 225 grams of oxygen gas is reacted with an excess of the other two reactants. c. If the actual yield of the experiment in (b) is 105 grams of HCN, calculate the percent yield. 20. When solutions of potassium iodide and lead (II) nitrate are combined, the products are potassium nitrate and lead (II) iodide. a. Write a balanced equation for this reaction, including (aq) and (s). b. Calculate the mass of precipitate produced when 50.0mL of 0.45M potassium iodide solution and 75mL of 0.55M lead (II) nitrate solution are mixed.

8 c. Calculate the volume of 0.50M potassium iodide required to react completely with 50.0mL of 0.50M lead (II) nitrate 21. A solution of 2.5 M H 2 SO 4 is reacted with 6.2 M NaOH a. Write a balanced equation. b. Calculate the volume of H 2 SO 4 required in milliters. c. Calculate the mass of the salt produced. Other AP Chemistry teachers recommend: 5 Steps to a 5, AP Chemistry, 2018 edition, by John Moore and Richard Langley AP Chemistry Crash Course, 2 nd edition, by Adrian Dingle Test Prep Workbook for AP Chemistry The Central Science 13 th edition, by Edward Waterman