AP WORKSHEET 0: Significant Figures
Transcription
AP WORKSHEET 0: Significant Figures
AP WORKSHEET 0: Significant Figures 1. Determine the number of significant figures in each of the following. (6) (a) 0.7680 (b) 1230.00 (c) 1000.01 (d) 120.0 (e) 1.09 x 104 (f) 0.0080060 2. Use a calculator to find the results of the following and then round the answer to the correct number of significant figures. (6) (a) 34.66 + 333.0 (b) 1.23 + 9.66 (c) 445 - 1.22 (d) 18.2 + 1.998 (e) 10.2 – 1.34 (f) 100 - 23 3. State the significant figure rule that is associated with “captive zeros”. (1) 4. State the significant figure rule that is associated with “leading zeros”. (1) 5. State the significant figure rule that is associated with “trailing zeros”. (1) 6. State the significant figure rule that is associated with addition and subtraction operations. (1) 7. State the significant figure rule that is associated with multiplication and division operations. (1) 1 8. Use a calculator to find the results of the following calculations and then round the answer to the correct number of significant figures. (6) (a) 12 x 11.45 (b) (1.23 x 103) x (6.4 x 102) (c) 5.233 x 6.324 (d) 34 / 22 (e) (1.8 x 105) / 14 (f) 100.23 / 5.22 9. Round each of the following to three significant figures. (6) (a) 167.789 (b) 0.0000456922 (c) 23.00567 (d) 3.4569 (e) 7903.0005 (f) 11.044 10. How many significant figures in each of the following? (6) (a) 654.001 nm (b) 6.02 x 1023 particles (c) 1.0079 g (d) 13 neutrons (e) 11.22201 mg (f) 0.004504 g 2 AP WORKSHEET 0: Unit Conversions This worksheet utilizes the conversions given at this web site http://www.onlineconversion.com 1. Perform the following conversions. In each case show the full, dimensional analysis. Source any conversion factors from the web site above. An example is given below. (6) Question: 3.00 cm to mm. Answer: 3.00 cm 10 mm = 30 mm 1 cm (a) 120 J to MJ (b) 3 m to cm (c) 400 miles to km (d) 25 hectares to acres (e) 34 inches to ft (f) 289 s to hrs 2. Perform the following conversions. In each case you do NOT need to show the full, dimensional analysis. Source any conversion factors from the web site above. (6) (a) 120000 J to kJ (b) 13 kg to lbs (c) 83.2 K to oC (d) 48 mins to ms (e) 34 oF to oC (f) 13.2 kg to lbs 1 3. Perform the following sequences of conversions. In each case show the full, dimensional analysis. Source any conversion factors from the web site above. An example is given below. (6) Question: 3.00 cm to m VIA mm. Answer: 3.00 cm 10 mm 0.001 m = 0.03 m 1 cm 1 mm (a) 679 nm to cm VIA m (b) 23 miles to m VIA km (c) 567 feet to m VIA yd (d) 12 L to UK gal VIA mL (e) 8 MJ to J VIA kJ (f) 418 s to hrs VIA min 2 AP WORKSHEET Unit 0: Inorganic Nomenclature I 1. The following compounds are all binary compounds. Give the name of each one. (6) (a) SrO (b) K2O (c) Na2S (d) Cs3P (e) AlCl3 (f) 2. Mg3N2 Some of the following name and formula combinations are incorrect. Identify the correct combinations. For the others, suggest corrected combinations. (13) (a) barium hydroxide, BaOH2 (b) sodium oxide, SoO2 (c) barium chloride, BCl 3 (d) strontium oxide SrO2 (e) boron trifluoride, BoFl6 (f) vanadium (III) chloride, VCl (g) magnesium oxide, MgO4 3. Write the name of the following compounds. Use Roman numerals in the names. (7) (a) FeI3 (b) MnCl2 (c) HgO (d) Cu2S (e) CuS (f) SnI4 (g) MnBr2 1 4. Write the name of each of the following. To help get the correct name, use the periodic table to determine which elements are metals, which are non-metals and which compounds should include Roman numerals in their names. (16) (a) N2Br5 (b) P2S5 (c) Ge2O3 (d) N2O5 (e) SiO2 (f) AlH3 (g) FeO (h) CuCl2 (i) OCl2 (j) XeF6 (k) RaCl2 (l) SeCl2 (m) PCl5 (n) Na3P (o) CuF (p) V2O5 2 AP WORKSHEET 0: Inorganic Nomenclature II Add either a name or a formula to complete each table. (100) 1. Potassium dichromate 2. Lithium sulfide 3. Potassium bromide 4. Cesium iodide 5. Calcium phosphide 6. Sodium fluoride 7. Strontium oxide 8. Beryllium sulfide 9. Magnesium bromide 10. Lithium oxide 11. Strontium chloride 12. Barium bromide 13. Magnesium sulfide 14. Magnesium iodide 15. Hydrogen fluoride (Hydrogen monofluoride) 16. Barium phosphide 17. Sodium hydrogen phosphate 18. Potassium chloride 19. Lithium nitride 20. Calcium sulfide 21. Rubidium oxide 22. Strontium nitride 23. Cesium phosphide 24. Magnesium carbonate 25. Beryllium sulfate 1 26. Dinitrogen Tetraoxide 27. Carbon dioxide 28. Mercury(I) chloride 29. Hydroiodic acid 30. Iodic acid 31. Perbromic acid 32. Hypobromous acid 33. Phosphorus pentachloride 34. Iodine monochloride 35. Antimony(III) fluoride 36. Bromine monofluoride 37. Bromine dioxide 38. Dinitrogen pentoxide 39. Carbon monosulfide 40. Tellurium dioxide 41. Phosphorus tribromide 42. Carbon tetraiodide 43. Vanadium(V) chromate 44. Zinc carbonate 45. Silver hydroxide 46. Vanadium(III) chromate 47. Mercury(II) iodide 48. Uranium(V) nitrate 49. Nickel (III) nitride 50. Sulfuric acid 2 51. ScCl3 52. HCl 53. PtO2 54. Sb(ClO3)5 55. GeS2 56. ZnO 57. VSO4 58. CuCl2 59. TiO2 60. NiN 61. Ni3(PO4)2 62. CoF3 63. Au2O3 64. Zn3P2 65. Cr(NO3)6 66. NaIO2 67. NaIO3 68. NaI 69. H2SO3 70. H2CO3 71. AlN 72. AlH3 73. Li3AsO4 74. NaCN 75. Na2O2 3 76. Li3PO3 77. KHCO3 78. HF 79. AuI2 80. KMnO4 81. Na2Cr2O7 82. Ag2CrO4 83. AgCl 84. NaCH3COO 85. RaF2 86. KSCN 87. FeS 88. Fe2(SO3)3 89. FeSO4 90. MgS 91. Na2S2O3 92. RbCl 93. Cu(OH)2 94. Mg3N2 95. Cu3N 96. LiH 97. K2O 98. K2O2 99. Li3N 100. DsCl3 4 AP WORKSHEET 0: Elements, Mixtures & Compounds 1. Classify each of the following as either, an element, a compound or a mixture. If you classify something as a mixture then also state whether it is a homogeneous or a heterogeneous mixture. (10) (a) Helium (b) Nitrogen (c) Pure water (d) Pure table salt (sodium chloride) (e) Flat (un-carbonated) Coca-Cola (f) Air (g) Fruit cake 2. If three, different samples of a particular compound are found to have exactly the same elemental % by mass, what does that tell us about; (a) the three samples in relation to one another? (2) (b) the purity of the three samples? (2) 1 4. Match the following particulate diagrams to the correct description. In each case a black circle and a red circle represent the atoms of different elements. (4) 1 2 3 4 5 A. A single, pure, monatomic element. B. A mixture of two elements. C. A single, pure compound. D. A mixture of two compounds. E. A mixture of an element and a compound. 2 AP WORKSHEET 01b: Empirical Formula 1. A common oxide of nitrogen contains 25.93% N. Deduce the empirical formula of the oxide. (2) 2. A compound that is usually used as a fertilizer can also be used as a powerful explosive. The compound has the composition 35.00% nitrogen, 59.96% oxygen and the remainder being hydrogen. What is its empirical formula? Given it is ionic, suggest a name for the compound. (3) 3. What are the empirical formulae for these compounds, that both contain five carbon atoms? (2) (a) C5H10 (b) C5H12 4. A substance has an empirical formula of CH2Br and a molar mass of 188 g mol-1. What is the molecular formula of the compound? (1) 1 5. The common pain medicine, Advil, contains the active ingredient Ibuprofen that has a molar mass of 206 g mol-1. Ibuprofen contains 75.73% C, 8.74% H, the remainder being oxygen. What are the empirical and molecular formulae for Ibuprofen? (4) 6. The molar mass of the common antibiotic oxytetracycline is found to be 460 g mol-1 and a 2.000 g sample contains 1.1478 g of carbon, 0.10435 g of H, 0.62609 g of oxygen and the remainder being nitrogen. What is the molecular formula of the oxytetracycline? (4) 2 AP WORKSHEET 01c: Isotopes and Mass Spectrometry 1. Many elements have a number of isotopes. (a) Define the term isotope. (2) (b) Complete the following table. (22) Row Isotope symbol Atomic # # Protons # Neutrons Mass # 13 1 C6 2 17 18 3 26 56 4 17 37 5 2 6 52 7 3 128 50 70 (c) Consider the 2nd and 4th row in the table. What three things do they have in common? (3) (d) Consider the 2nd and 4th row in the table. Give two differences? (2) (e) Naturally occurring Ni is found to have the following approximate isotopic abundance; 58 Ni 68%, 60Ni 26%, 62Ni 4.0% and 61Ni 2.0% Calculate the average relative atomic mass of Ni to two decimal places. (2) 1 2. The results taken from a mass spectrum of chlorine gas show peaks at m/z 35.00 and m/z 37.00 (The m/z peaks on a mass spectrum identify the different isotopes of an element that are present in the sample). (a) Given that the relative abundances of Cl 35.00 and Cl 37.00 are 77.50% and 22.50% respectively, calculate the average relative atomic mass of chlorine atoms to four significant figures. (2) (b) Suggest all the possible masses of CI2 molecules that are made when two chlorine atoms bond together. (3) (c) Which of the molecules you have suggested in (b) will be the most abundant? Explain your answer. (2) 2 3. Naturally occurring bromine molecules, Br2 have masses of 158, 160 and 162. They occur in the relative abundances 25.69%, 49.99% and 24.31% respectively. What is the average atomic mass of bromine atoms? What is the relative abundance of 79 Br and 81Br isotopes? (4) 4. An unknown element ‘Z’ is analyzed in a mass spectrometer and is found to have the following isotopes with the corresponding relative abundances. Isotope Z50 Z52 Z53 Z54 4.34 83.79 9.50 2.37 Relative abundance (a) Using the axis below, sketch the expected mass spectrum that these data would provide. Label the axes and pay attention to the size of any lines that you draw. (4) (b) Calculate the average atomic mass of Z and identify the element. (3) 3 5. Consider the following mass spectrum that was generated from the analysis of an element. Relative Abundance 100 24 25 26 27 28 29 m/z (a) What does the existence of only a single peak in the spectrum suggest about the element? (b) Identify the element. 6. Copper has an atomic mass of 63.5456 amu and has two stable isotopes. Copper-63 has a mass of 62.9296 amu, and copper-65 has a mass of 64.9278 amu. (a) Calculate the percent abundance of each isotope of copper. (b) Sketch the expected mass spectrum of the copper. 4