CHM2045 S13: Exam # MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Transcription

1 CHM2045 S13: Exam # MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What value of l is represented by a d orbital? A) 2 B) 1 C) 0 D) 3 2) Determine the shortest frequency of light required to remove an electron from a sample of Ti metal, if the binding energy of titanium is kj/mol. A) 4.74 x Hz B) 7.87 x Hz C) 2.11 x Hz D) 6.19 x Hz E) 1.27 x Hz 3) Choose the transition (in a hydrogen atom) below that represents the absorption of the shortest wavelength photon. A) n = 4 to n = 5 B) n = 6 to n = 3 C) n = 3 to n = 1 D) n = 1 to n = 2 E) n = 2 to n = 3 4) Choose the ground state electron configuration for Cr 3 +. A) [Ar] B) [Ar]4s 2 3d 6 C) [Ar]4s 1 3d 2 D) [Ar]3d 3 E) [Ar]4s 2 3d 1 5) Which of the following statements is TRUE? A) The principal quantum number (n) describes the shape of an orbital. B) The angular momentum quantum number (l) describes the the size and energy associated with an orbital. C) An orbital is the path that an electron follows during its movement in an atom. D) The magnetic quantum number (m l ) describes the orientation of the orbital. E) All of the above are true. 6) Place the following in order of increasing IE 1 (first ionization energy). N F As A) F < N < As B) As < N < F C) F < As < N D) As < F < N E) N < As < F A-3

2 7) Place the following in order of decreasing metallic character. P As K A) P > As > K B) K > As > P C) K > P > As D) As > K > P E) As > P > K 8) What are the possible values of l if n = 6? A) -5, -4, -3, -2, -1, 0, +1, +2, +3, +4, or +5 B) -4, -3, -2, -1, 0, +1, +2, +3, or +4 C) 0, 1, 2, 3, 4, or 5 D) 6 9) How many valence electrons do the alkali earth metals possess? A) 8 B) 1 C) 7 D) 6 E) 2 10) Calculate the energy change, in joules, that occurs when an electron is raised from the n = 3 to the n = 5 energy level of a hydrogen atom. A) B) C) D) E) ) Which ionization process requires the most energy? A) W2+(g) W3+(g) + e- B) W(g) W+(g) + e- C) W+(g) W2+(g) + e- D) W3+(g) W4+(g) + e- 12) Calculate the wavelength of a baseball (m = 155 g) moving at 32.5 m/s. A) m B) m C) m D) m E) m A-4

3 13) Choose the valence orbital diagram that represents the ground state of Zn. A) B) C) D) E) 14) Choose the statement that is TRUE. A) Core electrons effectively shield outer electrons from nuclear charge. B) Valence electrons are most difficult of all electrons to remove. C) Outer electrons efficiently shield one another from nuclear charge. D) Core electrons are the easiest of all electrons to remove. E) All of the above are true. Two electromagnetic waves are represented below. 15) Wave (a) has the A) shorter wavelength and lower energy than wave (b). B) longer wavelength and lower energy than wave (b). C) shorter wavelength and higher energy than wave (b). D) longer wavelength and higher energy than wave (b). A-5

4 16) Place the following elements in order of decreasing atomic radius. Xe Rb Ar A) Rb > Xe > Ar B) Ar > Xe > Rb C) Xe > Rb > Ar D) Rb > Ar > Xe E) Ar > Rb > Xe 17) Place the following types of electromagnetic radiation in order of increasing frequency. x-rays microwaves gamma rays A) microwaves < gamma rays < x-rays B) microwaves < x-rays< gamma rays C) gamma rays < x-rays < microwaves D) x-rays < gamma rays < microwaves E) gamma rays < microwaves < x-rays 18) What is the maximum number of s orbitals that are possible (for a given value of n)? A) 7 B) 3 C) 1 D) 9 E) 5 19) Place the following in order of decreasing radius. Te 2 F O 2 A) Te 2 > O 2 > F B) F > Te 2 > O 2 C) O 2 > F > Te 2 D) F > O 2 > Te 2 E) Te 2 > F > O 2 20) Calculate the wavelength (in nm) of a the red light emitted by a neon sign with a frequency of Hz. A) 492 nm B) 792 nm C) 164 nm D) 192 nm E) 610 nm 21) Give the number of valence electrons for Si. A) 2 B) 26 C) 28 D) 12 E) 4 22) Calculate the energy of the green light emitted, per photon, by a mercury lamp with a frequency of Hz. A) J B) J C) J D) J E) J A-6

5 23) The element that corresponds to the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 3 is. A) vanadium B) manganese C) iron D) scandium E) cobalt 24) Which of the following elements would you predict to have an anomalous (e.g., irregular d-orbital filling) electron configuration? A) Se B) Ag C) Sr D) Ca E) Cs 25) The greater the energy of a photon, the A) longer the wavelength and the lower the frequency. B) shorter the wavelength and the lower the frequency. C) shorter the wavelength and the higher the frequency. D) longer the wavelength and the higher the frequency. 26) Choose the valence orbital diagram that represents the ground state of Sr 2+. A) B) C) D) E) 27) The element that corresponds to the electron configuration [Ar] 4s 1 3d 5 is. A) chromium B) manganese C) iron D) vanadium E) titanium A-7

6 Answer Key Testname: CHM2045 S13 E01 1) A 2) B 3) D 4) D 5) D 6) B 7) B 8) C 9) E 10) D 11) D 12) D 13) E 14) A 15) C 16) A 17) B 18) C 19) A 20) E 21) E 22) E 23) A 24) B 25) C 26) E 27) A A-8