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Practice Questions

Topic 1

For questions 1-9, match the description with the correct sub atomic (s)

a. b. c. d. Proton & neutron e. Proton & electron c 1. Responsible for stabilizing the nucleus c 6. Does not have a charge; i.e. has a neutral a 2. Can be transferred or shared; responsible for charge chemical bonding between b 7. Attracts and holds to the b 3. Has a positive charge e 8. Creates Coulombic attraction d 4. Located in the nucleus a 9. Has a tiny that is practically zero d 5. Makes up most of the mass of an atom

10. How many does an atom of have? Beryllium as 4 protons 11. How many does an atom of have? Nitrogen has a mass of 14 and 7 protons, so 14-7=7 neutrons 12. How many neutrons are in an atom of cesium? Cesium has a mass of 133 and 55 protons, so 133-55= 78 neutrons 13. How many electrons are there in a neutral atom of sodium? There are 11 electrons in a neutral sodiim atom 14. How many electrons are there in a sodium ? Na loses 1 e- when it forms an ion, so there are 10 e- in a Na ion 15. How many electrons are in a neutral iodine atom? There are 53 e- in a neutral iodine atom 16. How many electrons are there in a iodide ion? Iodine gains 1e-, so there are 54 e- in an iodide ion 17. has two oxidation numbers, 2 and 3. How many electrons are in an ion of iron (II) and in an iron (III) 18. Whichion? of the four universal --note, this should introduce 24 e- 23e- questions 19-23--there is no answer for #18 For questions 10-22, match the universal with its role.Note the numbering error--- should be 19 through 22. 19. Hold together d a. Strong force 20. Holds the atom together b b. Electromagnetic force 21. Holds the nucleus together a c. Weak force 22. Hold in the nucleus together c d. Gravitational force

23. Rank those forces from strongest to weakest: strong, electromagnetic, weak, gravitational 24. Write the number 2,600,000,000 in scientific notation 2.6 x 10 9 25. Write the number 0.0000000000000000000000000642 in scientific notation 6.42 x 10 -26

Topic 2 questions

26. Forces that hold atoms together are intra molecular forces 27. Forces that hold compounds together are inter molecular forces

Use the table to the right to answer questions 28 & 29 28. Which list below correctly ranks the from lowest to highest boiling points? a. H2O  N2  O2  He c. He  H2O  N2  O2 b. N2  H2O  He  O2 d. He  N2  O2  H2O ***

29. Which list below correctly ranks the molecules from weakest to strongest intermolecular forces? a. H2O  N2  O2  He c. He  H2O  N2  O2 b. N2  H2O  He  O2 d. He  N2  O2  H2O *** 30. In order to freeze into ice, the molecules that make up have to: a. get hotter c. speed up b. get colder d. slow down *** Use the diagram for CO2 to answer the following questions 31 to 34:

31. To change dioxide from a to a you would need to ______. a. Increase the and/or decrease the *** b. Decrease the temperature and/or increase the pressure c. Decrease both the temperature and pressure d. Increase both the temperature and the pressure

32. Increasing the pressure around a liquid will… a. increase the boiling point of the liquid. *** b. decrease the boiling point of the liquid. c. not affect the boiling point of the liquid 33. To change from a liquid to a you would need to ______(hint: make sure you look closely at Figure 2 when choosing your answer). a. Increase the temperature and/or decrease the pressure b. Decrease the temperature and/or increase the pressure *** c. Decrease both the temperature and pressure d. Increase both the temperature and the pressure

34. Increasing the temperature of carbon dioxide from -100° C to -40° C at 1 atm of pressure would change it from a solid to a vapor. This process is known as a. Freezing b. Melting c. Condensation d. Sublimation***

Topic 3 questions

Figure 1 depicts energy levels in an atom of an unknown element that has been heated, and produced green, indigo, red, yellow, and violet color emissions. The direction of the arrow indicates which direction the electron moves.

35. Which arrow represents the electron gaining energy? a. a F b. b c. c d. d e. e f. f

Figure 1 9 36. Which arrow represents the transition that produced a green ? a. a d. d b. b B e. e c. c f. f 37. Which arrow represents the transition that produced an indigo photon? a. a A d. d b. b e. e c. c f. f 38. Which arrow represents the transition that produced a red photon? a. a d. d D b. b e. e c. c f. f 39. Which arrow represents the transition that produced a yellow photon? a. a d. d b. b e. e c. c C f. f 40. Which arrow represents the transition that produced a violet photon? a. a b. b c. c d. d e. e E f. f

Use Figure 3 to answer question 41.

41. Which spectral lines are showing blue shift and which ones are showing red shift? The spectral lines of A & D have shifted towards longer (RED), whil B & C have shifted to the BLUE Topic 4 questions 42. Summarize how the of , , and energy change as you move down a group and across a period. A complete answer will summarize how each trend relates to Coulombic attraction. Atomic radius increases as you move down a group, causing Coulombic attraction to decrease, because of this Coulombic attraction decrease and eletronegativity also decrease as you move down a group. 10 43. What is an ion? An ion is a charged atom with an uneven number of electrons because its lost or gained them 44. What type of do form? What type of ions do non-metals form? Metals form positive ions b/c they've

45. How many electrons and electron shells do each of the following elements have: lost electrons. Non-

a. 2 valence electons, 1 electron shells metals form negative b. Chlorine 7 valence electrons, 3 electron shells ions b/c they've gain Sodium c. 1 valence elctron, 3 electron shells electrons d. Calcium 2 valence electrons, 4 electron shells e. Sulfur 6 valence elctrons, 3 electron shells 46. Pick two different elements on the , and determine based on their positions, which one has the higher ionization energy and larger atomic radius. Answers will vary depending on the elements you chose, but that radius increases down, and decreases across. Ionization energy is opposite. Topic 5 47. Summarize the similarities and differences between ionic and covalent bonds. **Ionic bonds form through the transfer of electrons between cations (metals) and anions (non-metals). Their electronegativity difference is ~ greater than or equal to 1.7 ** Covalent bonds form through the the sharing of electrons between non-metals. Polar covalent bonds show electronegativity difference between 1.69 and 0.4; they display an uneven sharing of electrons. Non-polar bonds show an electronegativity difference less than or equal to 0.4, and evenly share electrons

48. What is the , and how can it be used to determine the number of electrons an atom will gain or lose when it becomes an ion? Atoms want to gain or lose electrons to stabilize, and the most stable elements are those with full valence shells: the Noble . All but Helium have 8 valence electrons, and the prefix for 8 is "oct-", hence the "octet rule." Metals have fewer valence electrons than non-metals, and its "easier" for them to lose electrons to stabilize and take on the of the closest , which are "behind" them on the periodic table. Non-metals are the opposite, they gain electrons to take on the configuration of the closest Noble gas, which are "in front" of them on the periodic table.

49. Be sure to complete the Naming Compounds and Acids worksheet to practice naming compounds and writing their . see answer key for that assignment

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