Name ________________________________________________ Pd _________ Date ______ AP Chemistry Review Questions Use these answers for questions 1 - 3. (A) O (B) La (C) Rb (D) Mg (E) N 1. What is the most electronegative element of the above? 2. Which element exhibits the greatest number of different oxidation states? 3. Which of the elements above has the smallest ionic radius for its most commonly found ion? Use these answers for questions 4 - 7. (A) 1s2 2s22p5 3s23p5 (B) 1s2 2s22p6 3s23p6 (C) 1s2 2s22p62d10 3s23p6 (D) 1s2 2s22p6 3s23p63d5 (E) 1s2 2s22p6 3s23p63d3 4s2 4. An impossible electronic configuration 5. The ground-state configuration for the atoms of a transition element 6. The ground-state configuration of a negative ion of a halogen 7. The ground-state configuration of a common ion of an alkaline earth element 8. Which of the following sets of quantum numbers (n, l, ml, ms) best describes the valence electron of highest energy in a ground-state gallium atom (atomic number 31) ? (A) 4, 0, 0, 1/2 (B) 4, 0, 1, 1/2 (C) 4, 1, 1, 1/2 (D) 4, 1, 2, 1/2 (E) 4, 2, 0, 1/2 9. All of the following statements concerning the characteristics of the halogens are true EXCEPT: (A) The first ionization energies (potentials) decrease as the atomic numbers of the halogens increase. (B) Fluorine is the best oxidizing agent. (C) Fluorine atoms have the smallest radii. (D) Iodine liberates free bromine from a solution of bromide ion. (E) Fluorine is the most electronegative of the halogens. Question 10-13 refer to atoms for which the occupied atomic orbitals shown to the right. 10. Represents an atom that is chemically unreactive 11. Represents an atom in an excited state 12. Represents an atom that has four valence electrons. 13. Represents an atom of a transition metal. 14. In the periodic table, as the atomic number increases from 11 to 17, what happens to the atomic radius? (A) It remains constant. (B) It increases only. (C) It increases, then decreases. (D) It decreases only. (E) It decreases, then increases. 15. The ionization energies for element X are listed in the table below. On the basis of the data, element X is most likely to be Ionization Energies for element X (kJ mol-1) (A) Na First Second Third Fourth Five (B) Mg 580 1815 2740 11600 14800 (C) AI (D) Si (E) P 16. Which of the following molecules has the shortest bond length? (A) N2 (B) O2 (C) Cl2 (D) Br2 (E) I2 17. For which of the following molecules are resonance structures necessary to describe the bonding satisfactorily? (A) H2S (B) SO2 (C) CO2 (D) OF2 (E) PF3 18. When writing electron configurations, which sublevel comes before the others? a. 2s b. 2p c. 3p d. 4p e. 4s 19. How many electrons can the d sublevel hold? a. 2 b. 6 c. 2n2 d. 10 e. 3 20. The Lewis dot structure of which of the following molecules shows only one unshared pair of valence electron? (A) Cl2 (B) N2 (C) NH3 (D) CCl4 (E) H2O2 21. The electron-dot structure (Lewis structure) for which of the following molecules would have two unshared pairs of electrons on the central atom? (A) H2S (B) NH3 (C) CH4 (D) HCN (E) CO2 22. When writing that an electron is in 3p, the 3 stands for a. the level b. the sublevel c. the orbital d. the electron spin 23. Which of the following has the least electronegativity? a. B b. Br c. Cs d. Cl e. Cu 24. Which of the following molecules is an exception to the octet rule? a. PF3 b. CCl4 c. CO2 d. SF6 e. H2O 25. How many valence electrons are in PO43-? a. 28 b. 64 e. 2 c. 32 d. 30 26. Write the electron configuration for neon. 27. State the charge for the following elements. (Make sure that you include both a number and a sign.) ______________A. oxygen ______________B. sodium ______________C. magnesium ______________D. aluminum ______________E. fluorine 28. Using electron configurations and the periodic table, write a paragraph to explain why nitrogen has an oxidation number of 3-. 29. What is the difference between ionic, nonpolar covalent, and polar covalent bonds? 30. What type of bonding would occur between: A. Sulfur (S) and Bromine (Br) ________________________ B. Sodium (Na) and Chlorine (Cl) _____________________ 31. Explain the relationship between bond energy and number of bonds. 32. Explain the relationship between bond length and number of bonds. 33. Draw the resonance structures for O3. 34. An FM radio station broadcasts at 99.7 MHz. Calculate the wavelength of the corresponding radio waves. 35. A photon of ultraviolet light possesses enough energy to mutate a strand of human DNA. For this reason, it is used to sterilize chemical goggles. What is the energy of a single photon and a mole of UV photons that have a wavelength of 250 nm? 36. Draw Lewis structures that obey the octet rule for each of the following: HCN POCl3 SCl2 XeO3 ONF 37. Calculate the formal charge of the central atom in each structure drawn for 36. If needed, write Lewis structures that involve minimizing the formal charge.