Chemistry for Engineering Students
4th Edition
ISBN: 9781337398909
Author: Lawrence S. Brown, Tom Holme
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 6, Problem 6.72PAE
6.72 LED bulbs offer a fairly new lighting alternative, and are becoming increasingly popular in home lighting. These bulbs combine excellent energy efficiency with the “warm” light and dimming ability of incandescent lights. Although LED bulbs are expensive, manufacturers claim that subsequent savings will more than offset the initial costs. Analyze the relative cost of incandescent versus LED lighting, assuming that the information in the table below is accurate. Are industry claims of cost savings justified?
LED Incandescent |
Initial cost $4.00 $0.75 Electricity usage 8 watts 60 watts Electricity cost $0.04/kwh $0.04/kwh Lifetime 25,000 hours 1,500 hours |
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionChapter 6 Solutions
Chemistry for Engineering Students
Ch. 6 - describe trace analysis and explain its role in...Ch. 6 - describe waves in terms of frequency, wavelength,...Ch. 6 - Prob. 3COCh. 6 - relate the frequency, wavelength, and amplitude of...Ch. 6 - describe the photoelectric effect by stating what...Ch. 6 - Prob. 6COCh. 6 - • use Planck’s equation to calculate the energy of...Ch. 6 - Prob. 8COCh. 6 - Prob. 9COCh. 6 - • describe similarities and differences between...
Ch. 6 - Prob. 11COCh. 6 - Prob. 12COCh. 6 - • identify an orbital (as 1s, 3p, etc.) from its...Ch. 6 - • list the number of orbitals of each type (1s,...Ch. 6 - • sketch the shapes of s and p orbitals and...Ch. 6 - • rank various orbitals in terms of size and...Ch. 6 - Prob. 17COCh. 6 - Prob. 18COCh. 6 - Prob. 19COCh. 6 - Prob. 20COCh. 6 - Prob. 6.1PAECh. 6 - 6.2 Unlike XRF, AAS cannot be used for...Ch. 6 - Prob. 6.3PAECh. 6 - Prob. 6.4PAECh. 6 - Prob. 6.5PAECh. 6 - Prob. 6.6PAECh. 6 - 6.7 Arrange the following regions of the...Ch. 6 - 6.8 Calculate the wavelength in meters, of...Ch. 6 - 6.9 If a string of decorative lights includes...Ch. 6 - 6.10 Define the term refraction.Ch. 6 - 6.11 Define the term photon.Ch. 6 - 6.12 Find the energy of a photon with each of the...Ch. 6 - 6.13 Place these types of radiation in order of...Ch. 6 - 6.14 For photon with the following energies,...Ch. 6 - Prob. 6.15PAECh. 6 - 6.16 Various optical disk drives rely on laser...Ch. 6 - 6.17 The laser in most supermarket barcode...Ch. 6 - 6.18 Assume that a microwave oven operates at a...Ch. 6 - 6.19 Fill in the blanks below to complete a...Ch. 6 - 6.20 When light with a wavelength of 58.5 nm...Ch. 6 - 6.21 The electron binding energy fur copper metal...Ch. 6 - Prob. 6.22PAECh. 6 - 6.23 Describe how the Bohr model of the atom...Ch. 6 - 6.24 According to the Bohr model of the atom, what...Ch. 6 - 6.25 Define the term ground state.Ch. 6 - 6.26 The figure below depicts the first four...Ch. 6 - 6.27 Refer w the data and energy-Ievel diagram...Ch. 6 - 6.28 A neon atom cmi light at many wavelengths,...Ch. 6 - 6.29 A mercury atom emits light at many...Ch. 6 - 6.30 How did the observation of electron...Ch. 6 - 6.31 Why do we use a wave function to describe...Ch. 6 - 6.32 What are the mathematical origins of quantum...Ch. 6 - Prob. 6.33PAECh. 6 - 6.34 Which of the following represent valid sets...Ch. 6 - 6.35 A particular orbital has n = 4 and l = 2....Ch. 6 - 6.36 Why are there no 2d orbitals?Ch. 6 - 6.34 What is the maximum number of electrons in an...Ch. 6 - 6.38 How many orbitals correspond to each of the...Ch. 6 - Prob. 6.39PAECh. 6 - 6.40 Referring to Figure 6.15, draw a 4p orbitals,...Ch. 6 - 6.41 Consider a 3d orbital. (a) What are the...Ch. 6 - Prob. 6.42PAECh. 6 - 6.43 Define the term spin paired.Ch. 6 - 6.44 On what does the Pauli exclusion principle...Ch. 6 - Prob. 6.45PAECh. 6 - Prob. 6.46PAECh. 6 - 6.47 Depict two ways to place electrons in the 2p...Ch. 6 - 6.48 Write the ground state electron configuration...Ch. 6 - 6.49 Which of these electron configurations are...Ch. 6 - 6.50 From the list of atoms and ions given,...Ch. 6 - Prob. 6.51PAECh. 6 - Prob. 6.52PAECh. 6 - Prob. 6.53PAECh. 6 - Prob. 6.54PAECh. 6 - 6.55 Explain why the s block of the periodic table...Ch. 6 - Prob. 6.56PAECh. 6 - Prob. 6.57PAECh. 6 - Prob. 6.58PAECh. 6 - Prob. 6.59PAECh. 6 - 6.60 Use the electron configurations of the alkali...Ch. 6 - 6.61 Using only a periodic table as a guide,...Ch. 6 - 6.62 Define the term ionization energy....Ch. 6 - 6.63 At which ionization for chlorine would you...Ch. 6 - 6.64 Arrange the following atoms in order of...Ch. 6 - Prob. 6.65PAECh. 6 - 6.66 Which element would you expect to have the...Ch. 6 - Prob. 6.67PAECh. 6 - 6.68 Indicate which species in each pair has the...Ch. 6 - 6.69 Compare the elements Na, B, Al, and C with...Ch. 6 - 6.70 Rank the following in order of decreasing...Ch. 6 - 6.71 Several excited states of the neon atom are...Ch. 6 - 6.72 LED bulbs offer a fairly new lighting...Ch. 6 - 6.73 How much energy could be saved each year by...Ch. 6 - Prob. 6.74PAECh. 6 - Prob. 6.75PAECh. 6 - Prob. 6.76PAECh. 6 - Prob. 6.77PAECh. 6 - Prob. 6.78PAECh. 6 - 6.79 How does the charge of electrons provide some...Ch. 6 - 6.80 Describe how valence electron configurations...Ch. 6 - 6.81 Why is there no element to the immediate...Ch. 6 - 6.82 A particular element has the following values...Ch. 6 - 6.83 The graph below shows the first three...Ch. 6 - 6.84 Which graph correctly depicts the first...Ch. 6 - 6.85 The visible lines in the hydrogen atom...Ch. 6 - 6.86 An excited He+ ion returns to the ground...Ch. 6 - Prob. 6.87PAECh. 6 - Prob. 6.88PAECh. 6 - Prob. 6.89PAECh. 6 - Prob. 6.90PAECh. 6 - 6.91 What is the only noble gas that does not have...Ch. 6 - 6.92 The photoelectric effect can he used to...Ch. 6 - 6.93 A mercury atom is initially in its lowest...Ch. 6 - Prob. 6.94PAECh. 6 - 6.95 A metallic sample is known to be barium,...Ch. 6 - 6.96 When a helium atom absorbs light at 58.44 nm,...Ch. 6 - 6.97 Arrange the members of each of the following...Ch. 6 - 6.98 Arrange the following sets of anions in order...Ch. 6 - 6.99 The photoelectric effect can he used in...Ch. 6 - 6.100 Some spacecraft use ion propulsion engines....Ch. 6 - 6.101 Laser welding is a technique in which a...Ch. 6 - Prob. 6.102PAECh. 6 - 6.103 Atomic absorption spectroscopy is based on...Ch. 6 - 6.104 The red color in fireworks is the result of...Ch. 6 - 6.105 When we say that the existence of atomic...Ch. 6 - 6.106 When Bohr devised his model for the atom,...Ch. 6 - Prob. 6.107PAE
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- 6.73 How much energy could be saved each year by replacing incandescent bulbs with LED bulbs? Assume that six 60-watt lamps are lit an average of three hours a night and they are each replaced with 8-watt LED bulbs. (See Problem 6.72.)arrow_forward6.101 Laser welding is a technique in which a tightly focused laser beam is used to deposit enough energy to weld metal parts together. Because the entire process can be automated, it is commonly used in many large-scale industries, including the manufacture of automobiles. In order to achieve the desired weld quality, the steel parts being joined must absorb energy at a rate of about 104 W/mm2. (Recall that 1 W = 1 J/s.) A particular laser welding system employs a Nd:YAG laser operating at a wavelength of 1.06m ; at this wavelength steel will absorb about 80% of the incident photons. If the laser beam is focused to illuminate a circular spot with a diameter of 0.02 inch, what is the minimum power (in watts) that the laser must emit to reach the 104 W/mm2 threshold? How many photons per second does this correspond to? (For simplicity, assume that the energy from the laser does not penetrate into the metal to any significant depth.)arrow_forwardIt requires 799 kJ of energy to break one mole of carbon-oxygen double bonds in carbon dioxide. What wavelength of light does this correspond to per bond? Is there any transition in the hydrogen atom that has at least this quantity of energy to one photon?arrow_forward
- Light Energy, and the Hydrogen Atom a Which has the greater wavelength, blue light or red light? b How do the frequencies of blue light and red light compare? c How does the energy of blue light compare with that of red light? d Does blue light have a greater speed than red light? e How does the energy of three photons from a blue light source compare with the energy of one photon of blue light from the same source? How does the energy of two photons corresponding to a wavelength of 451 nm (blue light) compare with the energy of three photons corresponding to a wavelength of 704 nm (red light)? f A hydrogen atom with an electron in its ground state interacts with a photon of light with a wavelength of 1.22 106 m. Could the electron make a transition from the ground state to a higher energy level? If it does make a transition, indicate which one. If no transition can occur, explain. g If you have one mole of hydrogen atoms with their electrons in the n = 1 level, what is the minimum number of photons you would need to interact with these atoms in order to have all of their electrons promoted to the n = 3 level? What wavelength of light would you need to perform this experiment?arrow_forwardA metallic element reacts vigorously with water, evolving hydrogen gas. An excited atom of this element has its outer electron in the 3p orbital. When this electron drops to its ground state in the 3s orbital, light is emitted of wavelength 589 nm What is the identity of the element? Explain how you arrived at your answer. What is the color of the emitted light?arrow_forwardHeated lithium atoms emit photons of light with an energy of 2.9611019 J. Calculate the frequency and wavelength of one of these photons. What is the total energy in 1 mole of these photons? What is the color of the emitted light?arrow_forward
- One bit of evidence that the quantum mechanical model is correct lies in the magnetic properties of matter. Atoms with unpaired electrons are attracted by magnetic fields and thus are said to exhibit pararamagnetism. The degree to which this effect is observed is directly related to the number of unpaired electrons present in the atom. Consider the ground-state electron configurations for Li, N, Ni, Te, Ba, and Hg. Which of these atoms would be expected to be paramagnetic, and how many unpaired electrons are present in each paramagnetic atom?arrow_forwardThe first-row transition metals from chromium through zinc all have some biologic function in the human body. How many unpaired electrons are present in each of these first-row transition metals in the ground state?arrow_forwardWhat is the maximum number of electrons that can be identified with each of the following sets of quantum numbers? In some cases, the answer may be none In such cases, explain why none is the correct answer. (a) n = 4, = 3, m = 1 (b) n = 6, = 1, m = 1, ms = 1/2 (c) n= 3, = 3, m = 3arrow_forward
- The table below is partially completed for subshells A and B, where subshell B is the next subshell higher in energy compared to subshell A. For example, if subshell A is the 4s subshell, then subshell B would be the 3d subshell. Use this criteria and the information provided to complete the table.arrow_forward6.71 Several excited states of the neon atom are important in the operation of a helium-neon laser. In these excited states, one electron of the neon atom is promoted from the 2p level to a higher energy orbital. An excited neon atom with a 1s22s22p55s1 electron configuration can emit a photon with a wavelength of 3391 nm as it makes a transition to a lower energy state with a 1s22s22p54p1 electron configuration. Other transitions are also possible. If an excited neon atom with a 1s22s22p53p1 electron configuration makes a transition to a lower energy state with a 1s22s22p53p1 electron configuration, it emits a photon with a wavelength of 632.8 nm. Find the wavelength of the photon that would be emitted in a transition from the 1s22s22p54p1 electron configuration to the 1s22s22p53p1 electron configuration. (It should help if you start by drawing an energy-level diagram.)arrow_forwardInvestigating Energy Levels Consider the hypothetical atom X that has one electron like the H atom but has different energy levels. The energies of an electron in an X atom are described by the equation E=RHn3 where RH is the same as for hydrogen (2.179 1018 J). Answer the following questions, without calculating energy values. a How would the ground-state energy levels of X and H compare? b Would the energy of an electron in the n = 2 level of H be higher or lower than that of an electron in the n = 2 level of X? Explain your answer. c How do the spacings of the energy levels of X and H compare? d Which would involve the emission of a higher frequency of light, the transition of an electron in an H atom from the n = 5 to the n = 3 level or a similar transition in an X atom? e Which atom, X or H, would require more energy to completely remove its electron? f A photon corresponding to a particular frequency of blue light produces a transition from the n = 2 to the n = 5 level of a hydrogen atom. Could this photon produce the same transition (n = 12 to n = 5) in an atom of X? Explain.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Chemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningChemistry for Engineering StudentsChemistryISBN:9781285199023Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningGeneral Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage Learning
- Chemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage LearningChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage Learning
Chemistry for Engineering Students
Chemistry
ISBN:9781337398909
Author:Lawrence S. Brown, Tom Holme
Publisher:Cengage Learning
Chemistry for Engineering Students
Chemistry
ISBN:9781285199023
Author:Lawrence S. Brown, Tom Holme
Publisher:Cengage Learning
General Chemistry - Standalone book (MindTap Cour...
Chemistry
ISBN:9781305580343
Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; Darrell
Publisher:Cengage Learning
Chemistry: An Atoms First Approach
Chemistry
ISBN:9781305079243
Author:Steven S. Zumdahl, Susan A. Zumdahl
Publisher:Cengage Learning
Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
Quantum Mechanics - Part 1: Crash Course Physics #43; Author: CrashCourse;https://www.youtube.com/watch?v=7kb1VT0J3DE;License: Standard YouTube License, CC-BY