Name ate lass HPTER 5 STUY GUIE FOR ONTENT MSTERY Electrons in toms Section 5.1 Light and Quantized Energy In your textbook, read about the wave nature of light. Use each of the terms below just once to complete the passage. amplitude energy frequency hertz light wave wavelength speed Electromagnetic radiation is a kind of (1) that behaves like a(n) (2) as it travels through space. (3) is one type of electromagnetic radiation. Other examples include X rays, radio waves, and microwaves. opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. ll waves can be characterized by their wavelength, amplitude, frequency, and (4). The shortest distance between equivalent points on a continuous wave is called a(n) (5). The height of a wave from the origin to a crest or from the origin to a trough is the (6). (7) is the number of waves that pass a given point in one second. The SI unit for frequency is the (8), which is equivalent to one wave per second. Use the figure to answer the following questions. 9. Which letter(s) represent one wavelength? 10. Which letter(s) represent the amplitude? Origin 11. If twice the length of passes a stationary point every second, what is the frequency of the wave? Study Guide for ontent Mastery hemistry: Matter and hange hapter 5 25
Name ate lass HPTER 5 STUY GUIE FOR ONTENT MSTERY Section 5.2 Quantum Theory and the tom In your textbook, read about the ohr model of the atom. Use each of the terms below to complete the statements. atomic emission spectrum electron frequencies ground state higher energy levels lower 1. The lowest allowable energy state of an atom is called its. 2. ohr s model of the atom predicted the of the lines in hydrogen s atomic emission spectrum. 3. ccording to ohr s atomic model, the smaller an electron s orbit, the the atom s energy level. 4. ccording to ohr s atomic model, the larger an electron s orbit, the the atom s energy level. 5. ohr proposed that when energy is added to a hydrogen atom, its moves to a higher-energy orbit. 6. ccording to ohr s atomic model, the hydrogen atom emits a photon corresponding to opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. the difference between the orbits it transitions between. associated with the two 7. ohr s atomic model failed to explain the of elements other than hydrogen. In your textbook, read about the quantum mechanical model of the atom. nswer the following questions. 8. If you looked closely, could you see the wavelength of a fast-moving car? Explain your answer. h 9. Using de roglie s equation, m which would have the larger wavelength, a slow-moving proton or a fast-moving golf ball? Explain your answer. Study Guide for ontent Mastery hemistry: Matter and hange hapter 5 27
Name ate lass HPTER 5 STUY GUIE FOR ONTENT MSTERY Section 5.3 Electron onfigurations In your textbook, read about ground-state electron configurations. Use each of the terms below just once to complete the passage. ufbau principle electron configuration ground-state electron configuration Hund s rule lowest Pauli exclusion principle spins stable The arrangement of electrons in an atom is called the atom s (1). Electrons in an atom tend to assume the arrangement that gives the atom the (2) possible energy. This arrangement of electrons is the most (3) arrangement and is called the atom s (4). opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. Three rules define how electrons can be arranged in an atom s orbitals. The (5) states that each electron occupies the lowest energy orbital available. The (6) states that a maximum of two electrons may occupy a single atomic orbital, but only if the electrons have opposite (7). (8) states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins occupy the same orbitals. omplete the following table. Element tomic Number Orbitals Electron onfiguration 1s 2s 2p x 2p y 2p z 9. Helium 1s 2 10. 7 11. Neon )( )( )( )( )( Study Guide for ontent Mastery hemistry: Matter and hange hapter 5 29
Name ate lass HPTER 5 STUY GUIE FOR ONTENT MSTERY Section 5.3 continued nswer the following questions. 12. What is germanium s atomic number? How many electrons does germanium have? 13. What is noble-gas notation, and why is it used to write electron configurations? 14. Write the ground-state electron configuration of a germanium atom, using noble-gas notation. In your textbook, read about valence electrons. ircle the letter of the choice that best completes the statement or answers the question. 15. The electrons in an atom s outermost orbitals are called a. electron dots. b. quantum electrons. c. valence electrons. d. noble-gas electrons. 16. In an electron-dot structure, the element s symbol represents the a. nucleus of the noble gas closest to the atom in the periodic table. b. atom s nucleus and inner-level electrons. c. atom s valence electrons. d. electrons of the noble gas closest to the atom in the periodic table. 17. How many valence electrons does a chlorine atom have if its electron configuration is [Ne]3s 2 3p 5? a. 3 b. 21 c. 5 d. 7 18. Given boron s electron configuration of [He]2s 2 2p 1, which of the following represents its electron-dot structure? a. e b. c. d. e 19. Given beryllium s electron configuration of 1s 2 2s 2, which of the following represents its electron-dot structure? a. e b. c. d. e opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 20. Which electrons are represented by the dots in an electron-dot structure? a. valence electrons c. only s electrons b. inner-level electrons d. both a and c 30 hemistry: Matter and hange hapter 5 Study Guide for ontent Mastery
Name ate lass HPTER 5 HPTER SSESSMENT Electrons in toms Reviewing Vocabulary Match the definition in olumn with the term in olumn. olumn olumn opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 1. The set of frequencies of the electromagnetic waves emitted by the atoms of an element 2. The minimum amount of energy that can be lost or gained by an atom 3. form of energy that exhibits wavelike behavior as it travels through space 4. three-dimensional region around the nucleus of an atom that describes an electron s probable location 5. The shortest distance between equivalent points on a continuous wave 6. The lowest allowable energy state of an atom 7. particle of electromagnetic radiation with no mass that carries a quantum of energy 8. The emission of electrons from a metal s surface when light of a certain frequency shines on it 9. figure indicating the relative sizes and energies of atomic orbitals escribe how each pair is related. 10. frequency, amplitude 11. valence electron, electron-dot structure a. wavelength b. photoelectric effect c. photon d. quantum e. atomic orbital f. atomic emission spectrum g. principal quantum number h. ground state i. electromagnetic radiation 12. principal energy levels, energy sublevels hapter ssessment hemistry: Matter and hange hapter 5 25
Name ate lass HPTER 5 HPTER SSESSMENT Understanding Main Ideas (Part ) ircle the letter of the choice that best completes the statement or answers the question. Use the following figure to answer questions 1 and 2. E 1. ccording to ohr s atomic model, which letter(s) in the figure represents a place where an electron cannot be? a. b., and E c. and d. 2. ccording to the quantum mechanical model of the atom, point E in the figure represents a a. point where an electron cannot be. c. position where an electron must be. b. position where an electron probably is. d. point beyond which no electron can go. opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 3. What can you conclude from the figure on the right? a. Hund s rule has been violated. b. The Pauli exclusion principle has been violated. c. The ufbau principle has been violated. d. This is a valid orbital diagram. 4. What can you conclude from the figure on the right? a. Hund s rule has been violated. b. The Pauli exclusion principle has been violated. c. The ufbau principle has been violated. d. This is a valid orbital diagram. )( ) ) )( 2s 1s )( 2s 1s )) )( 5. Which of the following can you conclude based on the de roglie equation? a. Waves behave like particles. c. ll matter has an associated wavelength. b. Most particles are electrons. d. ll matter behaves like particles. 6. Which of the following best describes the Heisenberg uncertainty principle? a. Light behaves like a particle and like a wave. b. The shorter the wavelength, the higher the frequency. c. It is impossible to know both the velocity and the position of a particle at the same time. d. You cannot measure an object without disturbing it. 2p 2p hapter ssessment hemistry: Matter and hange hapter 5 27
Name ate lass HPTER 5 HPTER SSESSMENT Thinking ritically nswer the following questions. 1. radio station has a frequency of 103.7 MHz. (1 MHz 10 6 s 1 ) What is the wavelength of the radiation emitted by the station? Indicate where this wavelength falls on the electromagnetic spectrum shown below. Electromagnetic Spectrum 10 5 10 6 10 7 10 8 10 9 10 10 10 11 10 12 10 13 10 14 10 15 10 16 10 17 10 18 10 19 (Hz) Radio M radio FM radio VHF-TV UHF-TV Microwave Infrared Visible Ultraviolet X rays rays 10 4 10 3 10 2 10 1 1 10 1 10 2 10 3 10 4 10 5 10 6 10 7 10 8 10 9 10 10 10 11 (m) 2. Look at the electromagnetic spectrum again. re the microwaves used to cook food higher or lower in frequency than radio waves? re microwaves longer or shorter in wavelength than radio waves? 3. Write the orbital diagram of aluminum. 4. Write the complete electron configuration and the noble-gas notation for aluminum. 5. Write the noble-gas notation for iodine. 6. Identify each atom. a. 1s 2 2s 2 2p 1 b. [r]4s 1 opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 7. Write electron-dot structures for the following atoms. a. neon c. carbon b. hydrogen d. sulfur 28 hemistry: Matter and hange hapter 5 hapter ssessment
Name ate lass HPTER 5 HPTER SSESSMENT pplying Scientific Methods chemist isolated four samples,,,, and. She obtained the following atomic emission spectra of the samples. 400 500 600 700 Nanometers 1. Examine each sample s atomic emission spectra. ssume that each sample represents a single element. What can you conclude by looking at the spectra? o the samples represent the same element or different elements? opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 2. Which part of the electromagnetic spectrum do the atomic emission spectra show? 3. Would the atomic emission spectrum for each sample change if you repeated the procedure? Explain your answer 4. What does each line in an atomic emission spectrum represent? hapter ssessment hemistry: Matter and hange hapter 5 29
HPTER 5 SUPPLEMENTL PROLEMS Electrons in toms 1. Orange light has a frequency of 4.8 10 14 s 1. What is the energy of one quantum of orange light? 6. List the sequence in which the following orbitals fill up: 1s, 2s, 3s, 4s, 5s, 6s, 7s, 2p, 3p, 4p, 5p, 6p, 7p, 3d, 4d, 5d, 6d, 4f, 5f. 2. Which is greater, the energy of one photon of orange light or the energy of one quantum of radiation having a wavelength of 3.36 10 9 m? 3. Use the relationships E h and c v to write E in terms of h, c, and. 4. radio station emits radiation at a wavelength of 2.90 m. What is the station s frequency in megahertz? 5. Record the frequency of your favorite radio station. What is the wavelength of the radiation emitted from the station? 7. Which element has the ground-state electron configuration [Kr]5s 2 4d 10 5p 4? 8. Which element has the ground-state electron configuration [r]4s 2 3d 10? 9. Write electron-dot structures for the following atoms. a. [Ne]3s 2 3p 3 b. [r]4s 2 3d 3 c. potassium opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 10. omplete the following table. Orbitals Element Symbol 1s 2s 2p x 2p y 2p z a. Nitrogen b. F )( )( )( )( ) c. arbon d. Electron onfiguration 1s 2 2s 2 2p 3 1s 2 2s 1 Supplemental Problems hemistry: Matter and hange hapter 5 7
HPTER 5 Electrons in toms Name: ate: In question 1, the speed of light, c, equals 3.00 10 8 m/s. 1 Yellow light has a wavelength of 5.60 10 7 meters. ccording to the formula, c =, what is the frequency of this yellow light? 5.36 10 14 s 1 5.36 10 16 s 1 1.87 10 15 s 1 1.87 10 15 s 1 This question covers TEKS 2. This question tests pages 119 121. Use the diagram below to answer question 2. 3 When a potassium compound is placed in a flame, energy is released and a violet color is produced. This energy release is due to the release of gamma rays from the nucleus the return of excited electrons to lower energy levels the movement of electrons to higher energy levels the absorption of photons by the electrons This question covers TEKS 6. This question tests pages 125 126. In question 4, Planck s constant, h, equals 6.626 10 34 J. s opyright Glencoe/McGraw-Hill, a division of The McGraw-Hill ompanies, Inc. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 wavelength 2 What is the wavelength of the wave shown above? 3.2 cm 3.5 cm 3.7 cm 4.0 cm This question covers TEKS 2. This question tests page 118. 4 ccording to Einstein, E photon = h. What is the energy of a photon if it has a frequency of 6.82 10 14 s 1? 9.72 10 20 J 1.03 10 20 J 4.52 10 19 J 4.52 10 20 J This question covers TEKS 2. This question tests pages 123 124. Reviewing hemistry: Mastering the TEKS hemistry: Matter and hange 9
HPTER 5 Electrons in toms, continued Name: ate: 5 Which of these is the ground-state electron configuration for an atom of fluorine (atomic number = 9)? 1s 2 2s 2 1s 2 2s 2 2p 3 1s 2 2s 2 2p 4 1s 2 2s 2 2p 5 This question covers TEKS 6. This question tests pages 135 139. 6 The electron configuration for an atom of iron is [r] 3d 6 4s 2. Which of the following is the correct electron-dot structure for iron? Fe Fe Fe Fe This question covers TEKS 6. This question tests pages 140 141. 7 Which of these orbital diagrams represents a chlorine atom in the ground state? hlorine has an atomic number of 17. 8 The arrangement of electrons in an atom of an element determines the chemical properties of that element. Our present-day understanding of how electrons are arranged in an atom is the result of all of these scientific contributions EXEPT 1s 2s 1s 2s 2p 2p 1s 2s 2p 3s 3p 1s 2s 2p 3s 3p This question covers TEKS 2 and 5. This question tests the material that was covered in the textbook on page 137. Rutherford s gold foil experiment that proved the existence of the nucleus ohr s orbits that explained hydrogen s quantized energy states e roglie s equation that led to thinking of electrons as both particles and waves Schrödinger s wave equation that predicted atomic orbitals This question covers TEKS 3 and 3E. This question tests the material that was covered in the textbook on pages 127 132. opyright Glencoe/McGraw-Hill, a division of The McGraw-Hill ompanies, Inc. 10 hemistry: Matter and hange Reviewing hemistry: Mastering the TEKS