Advanced Placement Chemistry ~ Summer Assignment Part 2 Name Topic 1: Measurements and Dimensional Analysis Appropriately read and report a measurement correctly with one uncertain digit. State the number of significant figures in a measurement. Identify a number as a measurement or an exact (or defined) value, and state that exact values have infinite significant figures. Write a number in both scientific notation and standard decimal notation. Carry out arithmetic operations (i.e. multiplication, division, addition, subtraction) with numbers in standard decimal notation and scientific notation, reporting the answer with the correct number of significant figures. Find the percent error of a measurement. Describe the accuracy or precision of a measurement or calculation. Use conversions to solve dimensional analysis problems. Explain density and use the density equation to find an unknown. 1. Count the number of significant figures in the following measurements: (a) 2.71 g (b) 0.00047 kg (c) 7.0 x 10 5 m (d) 1,030 L (e) 150 pencils (f) 37500 g (g) 0.1010 cm 2. Express each of the following in proper scientific notation. (a) 0.000125 m (c) 123,030,000 kg (b) 155.0 ml (d) 481.9 x 10-9 cm 3. Calculate the correct answer with proper units and significant figures for each of the following: (a) 12 g + 0.677 g + 86.33 g = (b) (355.78 g) / (0.056 L) = (c) 97.34 ml 34.1 ml = (d) 14.68 m x 5 m 2 = 4. Perform the following calculations with scientific notation and report your answer with the correct number of significant figures. (a) 0.14 x (6.02 x 10 23 ) = (b) (9.875 x 10 4 ) (9.795 x 10 4 ) x 100 % = 9.875 x 10 4 (assume 100 is exact) (c) (3.8 x 10-12 + 4.0 x 10-13 ) = (4 x 10 12 + 6.3 x 10 13 )
5. Solve the following problems using dimensional analysis. (a) A large railroad car is filled with 1745 gallons of milk. The car springs a leak in the bottom, and milk starts dripping out at a rate of 204.84 ml/sec. If the train is traveling at a speed of 65.4 miles per hour, calculate how many miles it will travel before all the milk has drained out of the car. (1 gal = 3.78 L, 1 mile = 5280 ft, 1 in = 2.54 cm) (b) The world record for the hundred meter dash is 9.77 seconds. What is the corresponding average speed in units of m/sec, km/hr, ft/sec, and miles/hr? 6. A rectangular block has dimensions of 2.9 cm x 3.5 cm x 10.0 cm. The mass of the block is 615.0 grams. What are the volume and the density of the block? 7. The density of pure silver is 10.5 g/ml at 20 C. If 5.25 grams of pure silver pellets are added to a graduated cylinder containing 11.2 ml of water, to what volume will the water in the cylinder rise? 8. The side of a 169.3 g aluminum cube was measured by Group A with the ruler shown on the right. (a) Record the measurement of the side of the cube. The ruler is 6+ cm long. Circle the uncertain digit. Explain why that is the uncertain digit. (b) Calculate the density of the aluminum cube in g/cm 3.
(c) Convert the density calculated in part b to units of lb/ft 3. (1 kg = 2.2046 lb, 1 ft = 12 in, 1 in = 2.54 cm) (d) If the accepted density of aluminum is 167 lb/ft 3, calculate the percent error of your calculated density. (e) Group B determined the density of the aluminum block to be 164 lb/ft 3. Describe the accuracy and precision of this calculation, compared to that of Group A. (f) Suppose the figure above shows the measurement of a square sheet of aluminum foil with a mass of 1.90 10 3 lb. Find the thickness of the aluminum foil in mm. Write your answer in scientific notation. (Use density of aluminum = 167 lb/ft 3.) Topic 2: Matter: Elements and Compounds Describe the three common states of matter macroscopically (i.e. their shape and volume) and molecularly (in terms of interparticle attractions and kinetic molecular theory). Categorize matter into mixtures and pure substances, and pure substances into elements and compounds. Define and explain terms that identify physical/chemical characteristics of matter. Determine whether a change or process is chemical or physical. Describe an atom using isotopic notation. Find the number of protons, neutrons, and electrons of an atom using atomic number, mass number, and charge. Calculate the average atomic mass of an element using abundance data of isotopes. Describe how the periodic table is organized in periods (1-7) and families/groups (alkali metals, etc.) List the seven diatomic elements. Categorize a compound as ionic, covalent, or an acid. Name and write formulas for ionic compounds, covalent compounds, and acids. 9. Define the following terms: (a) Solid (b) Liquid (c) Gas (d) Pure substance (e) Atom-
(f) Molecule- (g) Ion- (h) Formula unit- (i) Homogeneous mixture (j) Heterogeneous mixture (k) Chemical change (l) Physical change 10. Identify the following as a physical property, physical change, chemical property, or chemical change: (a) Ethanol has a density of 0.697 g/ml. (b) The solution turns blue upon mixing water and food coloring. (c) Wood burns in an oven. (d) Methyl alcohol is highly flammable. (e) Ice melts in a beaker. (f) Methyl ethanoate smells like apples. (g) Sugar dissolves in water. 11. What number of protons and neutrons are contained in the nucleus of each of the following atoms? Assuming each atom is uncharged, what number of electrons is present in each atom? (a) (b) (c) (d) 235 92 13 6 C U 57 26 Fe 208 82 Pb 12. Complete the following table: Name Mass # Atomic # # of Protons # of Neutrons Gallium 70 # of Electrons Isotope Notation 31 15 P 3 Strontium-80 55 25 Mn 2 13. List the 7 diatomic molecules:
14. An element consists of 1.40% of an isotope with a mass of 203.973 amu, 24.10% of an isotope with mass 205.9745 amu, 22.10% of an isotope with mass 206.9759 amu, and 52.40% of an isotope with mass 207.9766 amu. Calculate the average atomic mass and identify the element. 15. For each of the following compounds, classify it as an ionic compound, covalent compound, or an acid. Then write its name. H 2 SO 4 LiNO 3 Na 2 S P 4 O 10 Fe 2 O 3 HBr KClO 3 CuI N 2 O Sn 3 (PO 4 ) 2 H 2 S SO 3 Formula Type Name 16. For each of the following compounds, classify it as an ionic compound, covalent compound, or an acid. Then write its formula. Name Type Formula silver nitrate aluminum oxide dinitrogen tetroxide sulfurous acid magnesium nitride ammonium carbonate iodine heptachloride cobalt (III) sulfate lithium hydrogen carbonate zinc hydroxide oxygen difluoride hydrocyanic acid
Topic 4: Moles Calculate the molar mass of a compound and the percent composition of each element in a compound. Solve mole conversion problems using dimensional analysis. Determine the empirical and /or molecular formula of a compound. 17. Aspartame is an artificial sweetener that is 160 times sweeter than sucrose (table sugar) when dissolved in water. It is marketed as Nutra-Sweet. The molecular formula of aspartame is C 14 H 18 N 2 O 5. (a) Calculate the molar mass of aspartame. (b) Calculate the percent by mass for each element in aspartame. (c) Calculate the mass, in grams, of 1.56 mol of aspartame. (d) How many molecules are in 5.0 mg of aspartame? (e) How many atoms of nitrogen are in 1.2 g of aspartame? (f) What is the mass of one molecule of aspartame? 18. Phenol is a compound that contains 76.57% carbon, 6.43% hydrogen, and 17.0% oxygen. (a) Calculate the empirical formula.
(b) If its molar mass is 188 g/mol, what is its molecular formula? Topic 5: Reactions, Concentration, and Stoichiometry Write and balance chemical equations, including states of matter. Categorize a reaction as double replacement (DR), single replacement (SR), synthesis (S), decomposition (D), or combustion (C). Write the balanced molecular and net ionic equations for double replacement reactions, identifying the products formed (precipitate, gas, or water). Solve stoichiometry problems, including those that involve limiting and excess reactants. Determine the % yield, given the actual yield. 19. Write and balance the following equations: (a) Iron metal reacts with oxygen to form rust, iron (III) oxide. (b) Calcium metal reacts with water to produce aqueous calcium hydroxide and hydrogen gas. (c) Aqueous barium hydroxide reacts with aqueous sulfuric acid to produce solid barium sulfate and water. 20. For each of the following, identify the type of reaction and write the balanced molecular and net ionic equations. (a) Solutions of lead (II) acetate and hydrochloric acid are mixed. (b) A gaseous sample of propane, C 3 H 8, is burned in air. (c) A piece of aluminum foil is dipped in a solution of copper (II) chloride. (d) Solid magnesium oxide is strongly heated. (e) Solutions of potassium hydroxide and sulfuric acid are mixed. (f) Ammonia gas, NH 3, is formed from its elements.
21. The reusable booster rockets of the U.S. space shuttle employs a mixture of aluminum and ammonium perchlorate for fuel. A possible reaction for this is: Al(s) + NH 4 ClO 4 (s) Al 2 O 3 (s) + AlCl 3 (s) + NO(g) + H 2 0(g) (a) Balance the above reaction (b) If 4.0 g of aluminum reacted with 15.0 g of ammonium perchlorate, what would be the limiting reactant? How much excess reactant is left unreacted? (c) Using the above information, how much aluminum chloride would be produced in grams? (d) If you actually collected 4.18 g of aluminum chloride what would be your percent yield? 22. You add aluminum to a solution of copper (II) chloride and it reacts exothermically. Write the balanced equation below. (a) How much copper (II) chloride is needed to react with 1.25 g of Al? (b) How much of each product would you collect? 23. When 125.0 g of ethylene (C 2 H 4 ) burns in 60.0 grams of oxygen to give carbon dioxide and water, how many grams of CO 2 are formed?