Name Date: Chemistry 9 Weeks Exam Review Guide 9 Weeks Exam: Tuesday, October 15 th Topics Covered Unit 1 Measurement: Accuracy & Precision, metric system, Conversions, Significant Figures, Percent Error, Scientific Notation, Density, Dimensional Analysis with English/metric conversions Unit 2 Matter: Elements, Compounds, Pure Substances, Mixtures, Physical and Chemical Changes and Properties, heat, specific heat, lab safety and equipment Unit 3 The Atom Groups on the Periodic table, Atomic Structure, Atoms, Ions, Isotopes, Atomic Mass, characteristics of metals, and nonmetals Unit 4 Nuclear: types of radioactivity, nuclear equations, decay series, half-lives, transmutations, fission vs. fusion UNIT 1: Scientific Measurement (Chapter 3) 1. How many sig figs are in the following numbers? 2.04 0.002804 1,230 0.00989 2. When adding and subtracting, the rule for sig figs is to look at the number of. Calculate the following using correct sig figs: 18.345 + 4.12 = 21.672 0.5 = 3. When multiplying and dividing, the rule for sig figs is to look at the number of. Calculate the following using correct sig figs: 5.678 x 2.3 = 18.1 x 3 = 4. Put the following numbers in scientific notation: 8,923,000,000 = 0.00000345 = 0.00045 = 5. Do the following unit conversions: 6.7m = mm 325 kl = L 6. How many millimeters are in 765 centimeters? 7. How many centigrams are in 8.56 kilograms? 8. The formula for density is: Density is the ratio of to. 9. Calculate the density of an object if it has a mass of 13.2 grams and a volume of 3.4 liters.
Density = 10. Calculate the mass of a piece of plastic that has a density of 3.14 g/ml and a volume of 7.2 ml. Mass = 11. Calculate the volume of an unknown substance that weighs 23.1 grams and has a density of 5.6 g/ml. Volume = 12. What is the definition of density? 13. What is the difference between accuracy and precision? Accuracy: Precision: 14. Determine if the measurements below have good accuracy/ precision or both. The true volume is 31.0 ml 31.1mL, 31.0 ml, 31.2 ml 25.5 ml, 25.2 ml, 25.4 ml 27.3 ml 43.1 ml, 19.7 ml 15. Calculate the percent error: Experimental Length = 14.1 cm Accepted Length = 14.9 cm 16. Use dimensional analysis to convert 68.0 lbs to milligrams (1 kg = 2.2 lbs) UNIT 2: Matter and Change (Chapter 1 & 2) 17. What is a chemical change? Which of the following is a chemical change: ripping a piece of paper, melting ice, burning wood? 18. Give 2 examples of physical changes: 19. What is the difference between physical and chemical properties? Which of the following is NOT a physical property? color, boiling point, texture, density, reactivity 20. Name 2 chemical properties: 21. What is the difference between heterogeneous and homogeneous mixtures?
22. Which of the following is an example of a homogeneous mixture? copper, salsa, salt, Gatorade 23. Determine if each is a pure substance or a mixture: sodium (Na) Kool-Aid water 24. Name the 4 indicators of chemical change:,,, 25. Define heat: 26. Define specific heat: 27. What is the difference between endothermic and exothermic phase changes? 28. Convert the following: 38.65 cal = J 934 J = kcal 29. How much energy (in joules) is required to heat a piece of iron weighing 1.30g from 25.0 o C to 46.0 o C? 30. A 55.0g sample of a metal requires 675 J of energy to hear it from 25.0 o C to 118.0 o C. Calculate the specific heat of the metal. UNIT 3: Atomic Structure (Chapter 4 & 6) 31. Calculate the atomic mass of iron to the one-hundredths place value based on the following information: Fe-56 (94.5 %) Fe-57 (2.3 %) Fe-59 (3.2 %) 32. The mass number is found by adding plus. 33. What is the difference between a cation and an anion? (Which is positive/negative? Gained or lost e-?) Cation: Anion: 34. Nickel: Protons = Neutrons = Electrons = Chlorine: Protons = Neutrons = Electrons = 35. How many neutrons are in the following isotopes? Co-60 U-235 W-185 36. Name 2 noble gases:, Name 2 halogens:,
37. Give 3 examples of transition metals:,, 38. What do the numbers represent in the following symbol? 190 Os 76 190 = 76 = 39. The rows on the periodic table are called. The columns on the periodic table are called. 40. Write the correct charge and name for the following ions. Example: Calcium = Ca 2+ Calcium ion Sulfur = S 2- Sulfide Lithium = Fluorine = Magnesium = Nitrogen = 41. As Potassium becomes as ion, it likes to (gain/lose) electrons. How many? As Oxygen becomes an ion, it likes to (gain/lose) electrons. How many? 42. Sn-120: Protons = Neutrons = Electrons = 43. Atoms of the same element always have the same number of (protons, neutrons, electrons) 44. An isotope has 12 protons, 12 electrons, and 14 neutrons. Name the isotope using hyphen notation: 45. What are valence electrons? How many valence electrons are in each family? 46. Metals are located on the side of the periodic table, and tend to electrons to form. List three characteristics of metals: 47. Nonmetals are located on the side of the periodic table, and tend to electrons to form. List three characteristics of nonmetals: 48. List the metalloids: 49. Know the safety rules 50. Be able to identify the various lab equipment and know their uses.
UNIT 4: Nuclear Chemistry (Chapter 25) 51. Describe the type of shielding needed for alpha, beta, and gamma rays. Alpha: Beta: Gamma: 52. Complete the following transmutations: 14 N + 4 He 12 C + 4 He 14 N + 9 Be + 4 He 12 C + 53. The radioactive isotope Tc-99 has a half-life of 6 hours. If you were injected with 250 mg, how much would remain after 2 days? 54. Calculate the half-life of a radioactive isotope if a 325 gram sample decays to 5.08 grams in 422 days. 55. Show the GAMMA emission of the following isotopes: Po-210 W-185 56. Show BETA and GAMMA emission of the following isotopes: I-127 Mn-56 57. Show the electron capture for Cu-66. Au-198 58. Show the POSITRON emission of the following isotopes: Au-199 Ir-193 59. What is the difference between fission and fusion? Fission: Fusion:
60. An alpha particle consists of two protons and two electrons. TRUE or FALSE The emission of an alpha particle changes an isotope s mass. TRUE or FALSE The emission of a beta particle changes an isotope s mass. TRUE or FALSE A beta particle is an electron released from the nucleus. TRUE or FALSE A positron decreases the atomic number by 1 amu. TRUE or FALSE 61. What is a gamma ray? 62. Determine the isotope formed by the following decay of Th-232. alpha, beta, beta, alpha, alpha, alpha, alpha, beta, beta, alpha 63. What is the definition of half-life? 64. What is radioactivity? 65. What mass of Sr-90 remains of a 22.4 gram sample that decayed over a period of 123 days? The halflife of the isotope is 72 days.