1. Provide the correct number of significant figures for each of the following numbers.

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1 AP Chemistry Summer Assignment 2016 Admission into AP Chemistry is dependent on completion of each of the sections by the due dates posted on Google Classroom. Please scan and submit your work to Classroom in PDF format. An exam covering this material will be given on the second class day of the semester. A score of 60% or greater on the exam is highly recommended in order to continue in the course. Section I: Calculations and Basic Properties of Matter Unit conversion and dimension analysis is the breadandbutter of Chemistry, and you must be comfortable working with these tools regardless of the obscure units you may encounter. 1. Provide the correct number of significant figures for each of the following numbers. a. 7.32x10 2 e. 1.90x10 6 i b. 1.4x10 3 f j c g d. 17,000 h. 13, Round each of the following numbers to two significant figures and provide answers in scientific notation. a c. 76,900 b. 38,876,000 d Perform the following mathematical operations and express each result to the correct number of significant figures. a c.!.!"#!.!"#!"#.!!.! b x / 63 d. ( ) / A student performed an analysis of a sample for its magnesium content and obtained the following results: 28.63%, 28.62%, 28.59%, and 28.62%. The actual amount of magnesium in the sample is 25.8%. What conclusions can you draw about the accuracy and precision of these results? Use standard deviation and mean percent error in order to support your conclusion. 5. Calculate the percent error for the following measurements. a. The density of an aluminum block determined in an experiment was 2.64 g/cm 3. The literature value is 2.70 g/cm 3. b. The experimental determination of iron in an ore sample was 16.48%. Literature value is 16.12%. 6. Precious metals and gems are measured in troy weights in the English system: 24 grains = 1 pennyweight 20 pennyweights = 1 troy ounce 12 troy ounces = 1 troy pound 1 grain = gram 1 carat = gram a. Diamonds are measured in carats. If a lucky girl receives a 3.18 carat diamond, how many pennyweights is it? b. What is the mass of 2.3 troy ounces of gold in grams? c. The density of gold is 19.3 g/cm 3. What is the volume of a troy pound of gold?

2 7. Apothecaries use the following set of measures: 20 grains ap = 1 scruple 3 scruples = 1 dram ap 8 dram ap = 1 oz. ap 1 dram ap = 3.888g a. An aspirin tablet contains 5.00 x 10 2 mg of active ingredient. How many grains ap of active ingredient does it contain? b. From (a), how many scruples? c. What is the mass of 1.00 scruple in grams? 8. The current world record for the hundred meter dash is 9.58 s. What is the corresponding speed in the following units: a. m/s c. ft/s b. km/hr d. mi/hr How long would it take to run a mile (5820 ft) at this speed? 9. During a road trip, you pass a sign that says San Francisco 210 km. a. If you drive at a constant speed of 70 mi/hr, how long will it take you to reach San Francisco? b. If your car gets 34 miles to the gallon, how many liters of gasoline are necessary to travel 210 km? 10. You have a 1.0 cm 3 sample of lead and a 1.0 cm 3 sample of glass. You drop each in a separate beaker of water. How do the volumes of water displaced by each sample compare? Density lead = g/cm 3 Density glass = 3.00 g/cm A sibling is running a fever of F. a. What is the temperature on the Celsius scale? b. On the Kelvin scale? 15. The density of diamond is 3.51 g/cm 3. What is the volume of a 4.5 carat diamond? 1 carat = g. 16. The volume of an unearthed diamond is 2.8 ml. What is the mass of the diamond in carats? 17. A g sample of metal pellets are poured into a graduated cylinder initially containing 12.7 ml of water. If the water level rises to 21.6 ml, what is the density of the metal? 18. Two spherical objects have the same mass. One floats on water; the other sinks. Which object has the greater diameter? Explain your answer. 19. Explain several differences among the three physical states of matter (solid, liquid, and gas). 20. Classify each of the following as homogeneous or heterogeneous. a. soil b. air (the atmosphere) c. a carbonated beverage d. gasoline e. gold f. a solution of isopropyl alcohol and water.

3 21. Classify each of the following as a mixture or a pure substance. Of the pure substances, which are elements and which are compounds? a. water f. uranium b. blood g. baking soda (sodium bicarbonate) c. salt water h. wood d. iron i. table salt (NaCl) e. brass 22. There are several indications that a chemical reaction is occurring. Provide a list of at least 5 of them. 23. If you place a glass rod over a burning candle, the glass appears to turn black. What is happening to each of the following (physical change, chemical change, both, or neither) as the candle burns? Explain each answer. a. the wax b. the wick c. the glass rod 24. The properties of a mixture are typically averages of the properties of its components. The properties of a compound may differ dramatically from the properties of the elements that combine to produce the compound. For each process described below, state whether the material being discussed is most likely a mixture or a compound, and state whether the process is a chemical change or a physical change. a. An orange liquid is distilled, resulting in the collection of a yellow liquid and a red solid. b. A colorless, crystalline solid is decomposed, yielding a pale yellowgreen gas and a soft, shiny metal. c. A cup of tea becomes sweeter as sugar as added to it.

4 Section II: Nomenclature Just as being able to count something is important, it is more important that you be able to name the thing you are counting. Some basic expectations regarding nomenclature: you are expected to remember the names and charges of the polyatomic ions below, and as an extension, the names and symbols of many elements. You will also be expected to know which elements are diatomic (H 2, O 2, N 2, F 2, Cl 2, Br 2, I 2 ). This isn't because I am cruel and sadistic, but more because it is what is expected of you by the AP test. There are also three classes of compounds you are expected to name: ionic (nontransition metals), covalent, and ionic (with transition metals). Polyatomic ions to memorize: Group IIIB Group IVB Group VB Group VIB GroupVIIB charge charge 1 charge Borate BO 3 Carbonate CO 3 Silicate SiO 3 Nitrate NO 3 Nitrite NO 2 Phosphate PO 4 Phosphite PO 3 Arsenate AsO 4 Arsenite AsO 3 charge O Sulfate SO 4 Sulfite SO 3 Selenate SeO 4 Selenite SeO 3 Telurate TeO 4 Telurite TeO 3 F Perchlorate ClO 4 Chlorate ClO 3 Chlorite ClO 2 Hypochlorite ClO Perbromate BrO 4 Bromate BrO 3 Bromite BrO 2 Hypobromite BrO Periodate IO 4 Iodite IO 3 Iodite IO 2 Hypoiodite IO charge 1 charge Other important Polyatomic Ions to remember: Acetate C 2 H 3 O 2 Permanganate MnO 4 Chromate CrO 4 OH Dichromate Cr 2 O 7 Peroxide O 2 Cyanide CN Oxalate C 2 O 4 Bisulfite Bisulfate Bicarbonate Biphosphite HSO 3 HSO 4 HCO 3 HPO 3 HPO 4 Hydronium H 3 O + Thiosulfate S 2 O 3 Biphosphate Ammonium + NH 4 Tartrate C 4 H 4 O 6 Dihydrogen phosphite H 2 PO 3 Thiocyanate SCN Dihydrogen phosphate H 2 PO 4

5 Nomenclature practice: For names provide a formula, for formulas provide a name. 1. P 4 O ZnAt 2 3. SBr 6 4. CaF 2 5. P 2 S 3 6. carbon monoxide 7. sodium hydride 8. aluminum selenide 9. xenon hexafluoride 10. dinitrogen monoxide 11. KClO Pb(OH) Ca(MnO 4 ) N 2 O Ti(HPO 4 ) manganese (VII) oxide 17. francium dichromate 18. copper (II) dihydrogen phosphate 19. silver chromate 20. ammonium oxalate 21. (NH 4 ) 2 SO Ni 3 (PO 4 ) Fe(IO 2 ) NaBrO H 3 PO tartaric acid

6 Section IIIa: Stoichiometry It is all fun and good to convert widgets to doodads, and name fun compounds like 2,3,7,8tetrachlorodibenzopdioxin, but we need to be able to apply them to specific reactions in order to determine how much of X reactant is needed to produce a certain amount of Y product. In short, you must be able to move between a number of molecules to moles, and from moles to grams. To do this, you must also be able to balance and write equations of your own in addition to determining products. 1. Balance the following equations and predict the physical states of all compounds (I would suggest reading section IIIb below before starting) a. CO + O 2 CO 2 b. N 2 O 5 + H 2 O> HNO 3 c. PCl 5 + H 2 O H 3 PO 4 + HCl d. CH 4 + Br 2 CBr 4 + HBr e. C 5 H 10 O 2 + O 2 CO 2 + H 2 O f. Cr(OH) 3 + HClO 4 Cr(ClO 4 ) 3 + H 2 O g. KNO 3 KNO 2 + O 2 h. La 2 O 3 + H 2 O La(OH) 3 i. NCl 3 + H 2 O NH 3 + HOCl j. Mg 3 N 2 + HCl MgCl 2 + NH 4 Cl k. AgNO 3 + K 2 SO 4 Ag 2 SO 4 + KNO 3 l. Al(OH) 3 + H 2 SO 4 Al 2 (SO 4 ) 3 + H 2 O m. CH 3 NH 2 + O 2 CO 2 + H 2 O + N 2 n. (NH 4 ) 2 Cr 2 O 7 Cr 2 O 3 + N 2 + H 2 O Section IIIb: Reaction types and Solubility Rules Being able to predict the products of a chemical reaction by identifying the reaction type is crucial in Chemistry. We will be referring back to the following reactions constantly throughout the course: synthesis, decomposition, single displacement, double displacement, oxidationreduction (redox), acidbase, and combustion. In order to predict many reactions, you will need to know which components are undergoing a chemical change in solution chemistry this generally appears as the formation of an insoluble precipitate. Use the following solubility rules to determine which products in Section IIIa (1) will be solid, aqueous, or gaseous. We will keep working with these, but it is expected in the long run that these will be memorized. Salts containing alkali metals and ammonium are soluble. There are very few exceptions to this rule. Salts containing nitrate and acetate are usually soluble. Halide salts (containing Cl, Br, F, and I) are usually soluble. Exceptions: halide salts of silver, lead and mercury. Example: AgCl, PbBr 2, and Hg 2 Cl 2 are insoluble. Most silver salts are insoluble, except for AgNO 3 and AgC 2 H 3 O 2, which are soluble. Most sulfate salts are soluble. Exceptions: BaSO 4, PbSO 4, Ag 2 SO 4, and SrSO 4 are insoluble. Hydroxide group I salts are soluble (ex: KOH, NaOH). Group II hydroxide salts (Ca(OH) 2, Mg(OH) 2, Ba(OH) 2 are only slightly soluble. Hydroxide transition metal salts and Al 3+ are insoluble. Examples: Fe(OH) 3, Al(OH) 3, and Co(OH) 2 are insoluble. Most transition metal sulfides are highly insoluble. Examples: CdS, FeS, ZnS, Ag 2 S. Other sulfides such as with arsenic, antimony, bismuth, and lead are also insoluble. Most chromates, phosphates, and carbonates are frequently insoluble except when combined with alkali metals and ammonium.

7 2. For each of these problems, you will need to balance the equation correctly. If you are given amounts of both reactants, you will need to find the limiting reactant. Remember that when gases are involved, one mole of any gas at STP occupies 22.4 liters. If the reactions occur in solution, the concentration used is molarity (M), which is the number of moles of solute in one liter of solution. Solid calcium carbonate decomposes upon heating, producing calcium oxide and carbon dioxide gas. a. Write a balanced chemical equation for this reaction. b. How many grams of calcium oxide will be produced after 12.25g of calcium carbonate is completely decomposed? (ans: 6.86g CaO) c. What volume of carbon dioxide gas is produced from this amount of calcium carbonate at STP? (ans: 2.94L) Hydrogen gas and bromine gas react to form hydrogen bromide gas. a. Write a balanced chemical equation for this reaction b. 3.2g of hydrogen gas and 9.5g of bromine gas react. Which is the limiting reagent? c. How many grams of hydrogen bromide gas can be produced using the amounts in (b)? (ans: 9.7g HBr) d. How many grams of the excess reactant are left unreacted? (ans: 3.1g) e. What volume of HBr, measured at STP, is produced in (b)? (ans: 2.7L of HBr) When ammonia gas, oxygen gas and methane gas (CH 4 ) 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 g of oxygen gas is reacted with an excess of the other two reactants. (ans: 253.8g H 2 O and 127g HCN) c. If the actual yield of the experiment in (b) is 105g of HCN, calculate the percent yield. (ans: 82.7%) When solutions of potassium iodide and lead (II) nitrate are combined, the products are potassium nitrate and bright yellow lead (II) iodide. a. Write a balanced equation for this reaction, including physical states (solid, liquid, gas, aqueous). b. Calculate the mass of precipitate produced when 50.0 ml of 0.45M potassium iodide solution and 75mL of 0.55M lead (II) nitrate solution are mixed. (ans: 5.2g PbI 2 ) c. Calculate the volume of 0.50M potassium iodide required to react completely with 50.0mL of 0.50M lead (II) nitrate (ans: 100mL)

8 Section IV: Electron Structure and Periodicity The last topic involves notation of electron structure of atoms and properties related to positioning of elements on the periodic table (which heavily relies on electron structure). Trends you should be familiar with are valence electrons, electron shells, orbital notation, electron configuration, atomic radius, ionization energy, and electronegativity. Practice problems: 1. How many unpaired electrons are in arsenic? 2. Write the electron configuration for palladium. 3. How many valence electrons are in mercury? 4. Write the noble gas configuration for lead. 5. Which is more electronegative: sulfur or chlorine? Why? 6. Which has a larger atomic radius: potassium or bromine? Why? 7. Which has a smaller ionization energy: nitrogen or phosphorous? Why? 8. Write the noble gas electron configuration for copper.