Name Date. I suggest that you hold on to all the notes, textbook and lab reports from 10 th grade chemistry.

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1 Name Date Summer Assignment AP Chemistry Dr. Hussmann I hope you are as excited for another year of chemistry as I am! Here is some summer work to refresh your memory of the things we studied last year, and get you warmed up for this year. Your summer assignment includes reading, problems that complement the reading, and a few AP style problems. Before you dispose of all your 10 th grade material- read the following: I suggest that you hold on to all the notes, textbook and lab reports from 10 th grade chemistry. Enjoy your vacation. I suggest that you start your AP chemistry summer assignment around the first week of August so that the material will be fresh in your mind before starting AP classes! There are two parts to summer AP work: Reading assignment and the practice problems below. GO AND PURCHASE AN AP REVIEW BOOK. Barron s is my favorite and the one I have. It is succinct with plenty of extra practice with great organization. Purchase this to help you review concepts and units throughout the year as well as prepare for the AP exam. Many students find the condensed version really helps with preparing for tests, or boiling down material that is too dense elsewhere. Also, lots of extra practice problems if you need them! I suggest you pace yourself to read one packet a week, do at least two to three problems a day, and one AP problem a week. The first 4 chapters of the text book are mostly review from 10 th grade. Go through the chapter text and sample problems, make sure you fully understand the topics, and keep a list of any questions or topics you want to go over in class. Some of the topics we did not get a chance to cover in chemistry this year, but are relatively simple once you get the hang of it. Reading the book is a great way of taking your learning to the next level! Don t worry if you still have questions on these concepts- we will be going through anything that you are unsure of in the first weeks of class. I suggest thoroughly reading through the packets and working all problems in the packets. I have provided you with links to videos which go through the packets in a fun and easy to understand way. As with the text, keep a list of any questions or topics you want to go over in class.

2 You may work in a group as long as each of you understands the work done. You may contact me by over the summer, and I will do my best to answer your questions. See you next year and have a wonderful summer! Text: Chemistry: The Central Science, 13 th ed. T.L. Brown, H.E. LeMay, Jr., B.E. Bursten and J.R. Burdge, Upper Saddle River, N.J.: Prentice-Hall, 2014 Part 1: Reading Assignment to refresh your first year chemistry background 1. Review chapters 1-4, 20.1 and 20.2 of the text. This is, for the most part, your last year s material. Chapter 4 and 20.1 and 20.2 are introductions to all types of reactions and include balancing redox reactions, which will be a new concept. We will continue to practice this in class as well, but getting a head start on these reactions will make the start of the year much easier. 2. Read the packets provided & work all problems in the packets. The packets coincide with the material from chapter 1-4. If you are having difficulty, watch the following videos: Chemical foundations - vimeo.com/ Atoms, Molecules, and Ions - vimeo.com/ Stoichiometry vimeo.com/ , vimeo.com/ , vimeo.com/ Nomenclature, dimensional analysis and stoichiometry are central concepts and you must be ready to hit the ground running with them. Scientific notation and significant digits will be expected throughout AP work. So, chapter 3 is a very important chapter. Make sure you really understand moles, stoichiometry, and limiting reactants. Part 2: Answer the attached problems and following AP problems Ch.1: 1. The density of copper is 8.92 g/cm3. If a g sample is placed in a graduated cylinder that contains 15.0 ml of water, what is the total volume that would be occupied? 2. How many significant figures are in the following numbers? a c. 300,000 b d Perform the following conversions: a mL to L b. 5.0 x 10-8 m to cm c gal/hr to L/sec Ch 2:

3 grams (g) of wood are burned in oxygen. The products of this reaction weigh 74.4 g. (a) What mass of oxygen is needed in this reaction? (b) What mass of oxygen is needed to burn 8.00 lb of wood? 1 lb = g. 2. The isotopes 131 I and 60 Co are commonly used in medicine. Determine the number of neutrons, protons, and electrons in a neutral atom of each. 3. Complete the following table for neon. The average atomic mass of neon is amu. Isotope Percent Abundance (%) Atomic Mass (amu) 20Ne Ne Ne 4. Using a mass spectrometer, a scientist determined the percent abundances of the isotopes of sulfur to be 95.27% for 32 S, 0.51% for 33 S, and 4.22% for 34 S. Use the atomic mass of sulfur from the periodic table and the following atomic masses to determine whether these data are accurate, assuming that these are the only isotopes of sulfur: amu for 32 S, amu for 33 S, and amu for 34 S. 5. Write the empirical formula for each compound. a. Na 2S 2O 4 b. B 2H 6 c. C 6H 12O 6 d. P 4O Benzene (C 6H 6) is an organic compound, and KCl is an ionic compound. The sum of the masses of the atoms in each empirical formula is approximately the same. How would you expect the two to compare with regard to each of the following? What species are present in benzene vapor? a. melting point b. type of bonding c. rate of evaporation d. structure 7. Write the formula for each compound. a. dinitrogen monoxide b. silicon tetrafluoride c. boron trichloride d. nitrogen trifluoride 8. Name each compound. a. NbO 2 b. P 4S 10 c. Cu 2O d. ReF 5 Ch 3:

4 1. Write a balanced chemical equation for each reaction. a. Magnesium burns in oxygen. b. Aluminum reacts with hydrochloric acid. c. An aqueous solution of silver nitrate reacts with a solution of potassium chloride. d. Methane burns in oxygen. e. Sodium nitrate and sulfuric acid react to produce sodium sulfate and nitric acid. 2. What is the molecular or formula mass of each compound? a. potassium permanganate b. sodium sulfate c. hydrogen cyanide 3. What is the mass percentage of water in each hydrate? a. CaSO 4 2H 2O b. Fe(NO 3) 3 9H 2O c. (NH 4) 3ZrOH(CO 3) 3 2H 2O 4. A sample of a chromium compound has a molar mass of g/mol. Elemental analysis of the compound shows that it contains 68.43% chromium and 31.57% oxygen. What is the identity of the compound? 5. Which of the following has the greatest mass percentage of oxygen KMnO 4, K 2Cr 2O 7, or Fe 2O 3? 6. Two hydrates were weighed, heated to drive off the waters of hydration, and then cooled. The residues were then reweighed. Based on the following results, what are the formulas of the hydrates? Compound Initial Mass (g) Mass after Cooling (g) NiSO 4 xh 2O CoCl 2 xh 2O Calculate the number of moles in g of each substance. How many molecules or formula units are present in each sample? a. CaO (lime) b. CaCO 3(chalk) c. C 12H 22O 11 [sucrose (cane sugar)] 8. What is the total number of atoms in each sample? a g of HBr b g of CS 2 c g of NaOH 9. Phosphoric acid and magnesium hydroxide react to produce magnesium phosphate and water. If ml of 1.50 M phosphoric acid are used in the reaction, how many grams of magnesium hydroxide are needed for the reaction to go to completion?

5 10. Determine the mass of each reactant needed to give the indicated amount of product. Be sure that the chemical equations are balanced. a. AgNO 3(aq) + CaCl 2(s) AgCl(s) + Ca(NO 3) 2(aq); 1.25 mol of AgCl b. Pb(s) + PbO 2(s) + H 2SO 4(aq) PbSO 4(s) + H 2O(l); 3.8 g of PbSO The reaction of propane gas (CH 3CH 2CH 3) with chlorine gas (Cl 2) produces two monochloride products: CH 3CH 2CH 2Cl and CH 3CHClCH 3. The first is obtained in a 43% yield and the second in a 57% yield. a. If you use 2.78 g of propane gas, how much chlorine gas would you need for the reaction to go to completion? b. How many grams of each product could theoretically be obtained from the reaction starting with 2.78 g of propane? c. Use the actual percent yield to calculate how many grams of each product would actually be obtained. Ch 4: 1. Predict whether mixing each pair of solutions will result in the formation of a precipitate. If so, identify the precipitate. a. KOH(aq) + H 3PO 4(aq) b. K 2CO 3(aq) + BaCl 2(aq) c. Ba(NO 3) 2(aq) + Na 2SO 4(aq) 2. State whether each compound is an acid, a base, or a salt. a. NH 3 d. CH 3COOH b. NH 4Cl e. NaOH c. H 2CO 3 3. What are the products of an acid base reaction? Under what circumstances is one of the products a gas? 4. What is the ph of each solution? a mol of HNO 3 in 257 ml of water b mol of HI in 750 ml of water c mol of HClO 4 in 500 ml of water d mol of HBr in 5.00 L of water 5. How many moles of solute are contained in each? a ml of 1.86 M NaOH b ml of M HCl c ml of M HBr 6. In each redox reaction, determine which species is oxidized and which is reduced: a. Zn(s) + H 2SO 4(aq) ZnSO 4(aq) + H 2(g) b. Cu(s) + 4HNO 3(aq) Cu(NO 3) 2(aq) + 2NO 2(g) + 2H 2O(l) c. BrO 3 (aq) + 2MnO 2(s) + H 2O(l) Br (aq) + 2MnO 4 (aq) + 2H + (aq)

6 7. Balance each redox reaction under the conditions indicated. a. MnO 4 (aq) + S 2O 3 2 (aq) Mn 2+ (aq) + SO 4 2 (aq); acidic solution b. Fe 2+ (aq) + Cr 2O 7 2 (aq) Fe 3+ (aq) + Cr 3+ (aq); acidic solution c. Fe(s) + CrO 4 2 (aq) Fe 2O 3(s) + Cr 2O 3(s); basic solution d. Cl 2(aq) ClO 3 (aq) + Cl (aq); acidic solution e. CO 3 2 (aq) + N 2H 4(aq) CO(g) + N 2(g); basic solution 8. Calculate the number of grams of solute in L of each solution. a M BaI 2 c M NH 4Br b M Na 2SO 4 d M sodium acetate 9. A ml sample of a 1.07 M solution of potassium hydrogen phthalate (KHP, formula mass = g/mol) is diluted to ml. What is the molarity of the final solution? How many grams of KHP are in the ml sample? AP Problems: 1. An organic compound was synthesized and found to contain only C, H, N, O, and Cl. It was observed that when a g sample of the compound was burned, it produced g of CO 2 and g of H 2O. All the nitrogen in a different g sample of the compound was converted to NH 3, which was found to have a mass of g. Finally, the chlorine in a g sample of the compound was converted to AgCl. The AgCl, when dried, was found to weigh g. (a) Calculate the percent by mass of each element in the compound. (b) Determine the empirical formula for the compound. BeC2O4 3H2O(s) BeC2O4(s) + 3 H2O(g) 2. Answer the following questions about BeC2O4(s) and its hydrate. (a) Calculate the mass percent of carbon in the hydrated form of the solid that has the formula BeC2O4 3H2O. (b) When heated to 220. C, BeC2O4 3H2O(s) dehydrates completely as represented by the equation below. If 3.21 g of BeC2O4 3H2O(s) is heated to 220. C calculate: i. the mass of BeC2O4(s) formed, and, ii. the volume of the H2O(g) released, measured at 220. C and 735 mm Hg 3. A sample of dolomitic limestone containing only CaCO 3 and MgCO 3 was analyzed. (a) When a gram sample of this limestone was decomposed by heating, 75.0 milliliters of CO 2 at 750 mm Hg, and 20 C were evolved. How many grams of CO 2 were produced?

7 (b) Write independent equations of decomposition of each carbonate described above. (c) It was also determined that the initial sample contained gram of calcium. What percent of the limestone by mass was CaCO 3? (d) How many grams of the magnesium-containing product were present in the sample in part (a) after it had been heated? 4. An experiment is performed to determine the empirical formula of a copper iodide formed by direct combination of elements. A clean strip of copper metal is weighed accurately. It is suspended in a test tube containing iodine vapor generated by heating solid iodine. A white compound forms on the strip of copper, coating it uniformly. The strip with the adhering compound is weighed. Finally, the compound is washed completely from the surface of the metal and the clean strip is dried and reweighed. Mass of clean copper strip Mass of copper strip and compound Mass of copper strip after washing grams grams grams (a) State how you would use the data above to determine each of the following: i. The number of moles of iodine that reacted ii. The number of moles of copper that reacted (b) Explain how you would determine the empirical formula for the copper iodide. (c) Explain how each of the following would affect the empirical formula that could be calculated: i. Some unreacted iodine condensed on the strip ii. A small amount of the white compound flaked off before weighing