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Introduction to Chemistry, 4E (Russo) Chapter 4 the Modern Model of the Atom

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Introduction to Chemistry, 4e (Russo) Chapter 4 The Modern Model of the Atom 4.1 Multiple-Choice Questions 1) What is the main difference between "classical physics" and "quantum physics"? A) Quantum physics requires the speed of light to be a constant value. B) Classical physics requires that only certain, allowed values for energy be used. C) Quantum physics requires that only certain, allowed values for energy be used. D) Quantum physics can only describe the behavior of very small objects, like atoms and molecules. Answer: C Topic: Section 4.2 2) For the electron of a hydrogen atom, which of the following quantum "jumps" requires the most energy? A) from n = 3 to n = 4 B) from n = 2 to n = 3 C) from n = 4 to n = 5 D) from n = 1 to n = 2 Answer: D Topic: Section 4.4 3) Which feature of Bohr's atomic model is no longer accepted as true by today's scientists? A) that most of an atom's mass is located within the nucleus B) that electrons have only certain, allowed energy values C) that electrons orbit the nucleus in circular paths D) that each principal quantum level can hold a maximum of 2n2 electrons Answer: C Topic: Section 4.3 4) Which of the following subshells does not appear in the third shell? A) s B) p C) d D) f Answer: D Topic: Section 4.5 5) Which of the following subshells appear in the second shell? A) s B) s,p C) s, p, d D) p Answer: B Topic: Section 4.5 1 Copyright © 2011 Pearson Education, Inc. 6) The correct order of increasing energy in the following subshells is: A) 2p, 3s, 4s, 3p, 3d B) 2p, 3s, 3p, 4s, 3d C) 2p, 3s, 3p, 3d, 4s D) 2p, 3s, 3d, 3p, 4s Answer: B Topic: Section 4.5 7) How many electrons can be "stored" in a completely filled 4f sublevel? A) 14 B) 10 C) 7 D) 28 Answer: A Topic: Section 4.5 11) The total number of electrons that can be accommodated in 3d is ________. A) 5 B) 2 C) 6 D) 10 Answer: D Topic: Section 4.6 13) Which of the following anions will have the electronic configuration 1s22s22p63s23p6 ? A) K1- B) Cl1- C) S2- D) Br1- Answer: B Topic: Section 4.7 15) The likely formula of the compound formed between Ca and O is ________. A) Ca2O B) CaO2 C) Ca2O3 D) CaO Answer: D Topic: Section 4.7 16) Which of the following elements never obeys the octet rule? A) Hydrogen B) Nitrogen C) Carbon D) Chlorine Answer: A Topic: Section 4.7 17) Which is the correct electronic configuration for Se (atomic number 34) in the ground state? 2 Copyright © 2011 Pearson Education, Inc. A) 1s22s22p63s23p63d104s24p4 B) 1s22s22p63s23p63d104s04p6 C) 1s22s22p63s23p64s23d104p4 D) 1s22s22p63s23p63d104s03p6 Answer: C Topic: Section 4.5 19) Which of the following species does not match the electronic configuration 1s22s22p63s23p64s23d104p6 ? A) Br- B) Sr+2 C) As-3 D) Se+2 Answer: D Topic: Section 4.7 20) Which species has the following electronic configuration: 1s22s22p63s23p6 ? A) F- B) Mg+2 C) P-3 D) S- Answer: C Topic: Section 4.7 22) Which of the following does not have the neon electron configuration? A) S4+ B) Mg2+ C) O2- D) Al3+ Answer: A Topic: Section 4.7 23) The scientist credited with developing the current mathematical model of the atom is ________. A) Bohr B) Schrodinger C) Planck D) Rutherford Answer: B Topic: Section 4.8 24) Which of the following does not include [Kr] in its shorthand electron configuration? A) Sr2+ B) Te2- C) Se6+ D) Mo Answer: C Topic: Section 4.7 3 Copyright © 2011 Pearson Education, Inc. 25) Atoms in which of the following groups will likely gain three electrons? A) IIIA B) VA C) VIIA D) both A and B Answer: B Topic: Section 4.7 27) The relative ratio of atoms in the binary compound AlxOy is ________. A) x=2, y=3 B) x=3, y=2 C) x=5, y=2 D) x=2, y=5 Answer: A Topic: Section 4.7 28) The size of boron is ________ than that of oxygen and ________ than that of aluminum. A) smaller; larger B) larger; larger C) smaller; smaller D) larger; smaller Answer: D Topic: Section 4.6 29) Which orbital is dumbbell-shaped? A) 2s B) 3p C) 4d D) 5g Answer: B Topic: Section 4.8 30) Which orbital is a spherical shape? A) 2s B) 3p C) 4d D) 5f Answer: A Topic: Section 4.8 31) What is the number of outer shell electrons in fluorine? A) 2 B) 5 C) 7 D) 9 Answer: C Topic: Section 4.5 32) How many valence electrons are in silicon? 4 Copyright © 2011 Pearson Education, Inc. A) 2 B) 4 C) 5 D) 7 Answer: B Topic: Section 4.5 33) The valence shell ________. A) always contains eight electrons B) is the lowest energy shell in an atom C) is the outermost occupied shell in an atom D) is always the same for anions and cations Answer: C Topic: Section 4.7 34) Below are four pairs of atoms and ions. In which pair is the larger of the two species written first? A) S2- and S B) Cu2+ and Cu C) O and O2- D) Cr3+ and Cr Answer: A Topic: Section 4.7 35) The ion that has 14 protons and 18 electrons is ________. A) Si4+ B) Si4- C) N4+ D) N4- Answer: B Topic: Section 4.7 36) Which of the following has attained a noble gas electronic configuration? A) Si4+ B) Cl1+ C) Al3- D) Cr3+ Answer: A Topic: Section 4.7 37) Which color light is composed of photons having the largest energy? A) blue B) green C) yellow D) red Answer: A Topic: Section 4.1 38) Which type of electromagnetic radiation is composed of photons having the largest energy? 5 Copyright © 2011 Pearson Education, Inc. A) microwaves B) radio waves C) x rays D) gamma rays Answer: D Topic: Section 4.1 40) The elements of Group VIIIA are almost entirely non-reactive with any of the other chemical elements. Which of the following statements best explains this observed behavior? A) Group VIIIA elements comply with the octet rule. B) Group VIIIA elements are so rare that no one has ever studied their reactive properties in any detail. C) Group VIIIA elements are all gases, and gases are generally non-reactive. D) No explanation given here can explain why Group VIIIA elements do not react with any of the other chemical elements. Answer: A Topic: Section 4.7 41) What is the trend in atomic size in the series of Group IIA elements Be through Ra? A) Atomic size increases in this series. B) Atomic size decreases in this series. C) Atomic size remains unchanged in this series. D) Atomic size increases at first, then decreases in this series. Answer: A Topic: Section 4.6 42) Predict the formula of the compound produced in a reaction between barium (Ba) and oxygen (O). A) BaO2 B) BaO C) BaO2 D) Ba2O3 Answer: B Topic: Section 4.7 43) Predict the formula of the compound produced in a reaction between lithium (Li) and phosphorus (P). A) LiP B) Li2P3 C) LiP2 D) Li3P Answer: D Topic: Section 4.7 44) What is the wavelength (in meters) of radio waves that have a frequency of 89.9 MHz? (wavelength × frequency = speed of light; speed of light = 3 × 108 meters/sec.) A) 3.34 centimeters B) 2.70 × 1016 millimeters C) 0.300 meters D) 3.34 meters Answer: D 6 Copyright © 2011 Pearson Education, Inc. Topic: Section 4.1 45) Calculate the energy in joules of microwave radiation of wavelength 12.7 centimeters. (E = hν, h = 6.63 × 10-34 J sec; speed of light = wavelength × ν, speed of light = 3 × 108 meters/sec.) A) 4.87 × 1019 J B) 7.30 × 10-19 J C) 3.61 × 10-18 J D) 1.56 × 10-24 J Answer: D Topic: Section 4.1 46) In a single atom, what is the maximum number of electrons that can have quantum number n=4? A) 10 B) 14 C) 18 D) 32 Answer: D Topic: Section 4.3 47) The units of h (Planck's constant) are ________. A) J.s B) J/s C) m/s D) J/nm Answer: A Topic: Section 4.1 49) Which of the following elements is the smallest size chalcogen? A) H B) N C) O D) F Answer: C Topic: Section 4.8 50) Which of the following elements is the largest size halogen? A) He B) Br C) F D) Kr Answer: B Topic: Section 4.7 7 Copyright © 2011 Pearson Education, Inc. 4.2 True/False Questions 1) Bohr's atomic theory places an atom's electrons in discrete-energy circular paths around a central, positively charged nucleus. Answer: TRUE Topic: Section 4.3 3) The only possible way for an excited state electron to return to the ground state is to emit energy in the form of visible light. Answer: FALSE Topic: Section 4.1 4) Atoms tend to increase in size as one moves from left to right across a period. Answer: FALSE Topic: Section 4.6 6) The f-block represents a region on the periodic table which is 10 elements in width. Answer: FALSE Topic: Section 4.5 7) The p-block represents a region on the periodic table which is 6 elements in width.
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