Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. John Singer, Jackson Community College Chemistry for Changing Times, Fourteenth Edition Lecture Outlines Chapter 3 Atomic Structure Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Learning Objectives Explain the electrical properties of an atom. (3.1) Describe how the properties of electricity explain the structure of atoms. (3.1) Describe the experiments that led to the discovery of X-rays and an explanation of radioactivity. (3.2) Distinguish the three main kinds of radioactivity: alpha, beta, and gamma. (3.3) Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Learning Objectives Sketch the nuclear model of the atom, and identify its parts. (3.4) List the particles that make up the nucleus of an atom, and give their relative masses and electric charges. (3.5) Identify elements and isotopes from their nuclear particles. (3.5) Define quantum. (3.6) Arrange the electrons in a given atom in energy levels (shells). (3.6) Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Learning Objectives Relate the idea of a quantum of energy to an orbital. (3.7) Write an electron configuration (in subshell notation) for a given atom. (3.7) Describe how an elements electron configuration relates to its location in the periodic table. (3.8) Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Learning Objectives Distinguish the conversion of solar energy into electrical energy in a solar cell from the conversion of solar energy into the chemical-bond energy of a solar fuel. Explain why splitting water into the elements hydrogen and oxygen requires an energy input and why producing water by the reaction of hydrogen and oxygen releases energy. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electricity and the Atom Electrolyte: A compound that conducts electricity when molten or dissolved in water. Electrodes: Carbon rods or metallic strips that carry electrical current. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electrolysis Anode: A positive electrode. Cathode: A negative electrode. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Ions Ion: An atom or group of atoms with a charge. Anion: A negative ion. Cation: A positive ion. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Cathode-Ray Tubes Mid-1800s: Crookess tube Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Thomson Experiment 1897, Joseph John Thomson: Thomson determined the mass-to-charge ratio of cathode rays; discovering the electron. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Goldsteins Experiment 1886, Goldstein: observed positive rays using a perforated cathode. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Charge 1909, Robert Millikan: Using the oil-drop experiment, Millikan determined the charge of an electron. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. X-Rays 1895, Wilhem Roentgen: Using a cathode ray tube, Roentgen discovered X-rays. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Radioactivity 1895, Antoine Becquerel: Becquerel discovered radioactivity. During the following decade and a half, Marie and Pierre Curie worked to isolate pure radioactive substances. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Three Types of Radioactivity Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Three Types of Radioactivity Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Rutherfords Gold Foil Experiment In 1911, Ernest Rutherford published a paper in which he detailed his Gold Foil Experiment. Using an apparatus similar to that shown below, Rutherford discovered the atomic nucleus. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Rutherfords Gold Foil Experiment Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Subatomic Particles Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Atomic Structure Atomic number: The number of protons in a nucleus. Mass number: The sum of protons and neutrons in a nucleus. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Isotopes Isotopes have the same atomic number, but have different mass numbers (same number of protons, but different number of neutrons). Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Nuclear Symbol A ZA Z x = Element symbol A = Mass number Z = Atomic number x Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Bohr Model Flame tests: Different elements give different colors to a flame. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Bohr Model Continuous spectra: When light emitted from a solid substance passes through a prism, it produces a continuous spectrum of colors. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Bohr Model Line spectra: When light from a gaseous substance passes through a prism, it produces a line spectrum. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Bohr Model Quantum: A tiny unit of energy produced or absorbed when an electron makes a transition from one energy level to another. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Bohr Model When electrons are in the lowest energy state, they are said to be in the ground state. When energy from a flame or other source is absorbed by the electrons, they are promoted to a higher energy state (excited state). When an electron in an excited state returns to a lower energy state, it emits a photon of energy, which may be observed as light. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement Energy states or levels are sometimes called shells. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model The quantum model of the atom is a probability-based model. It is composed of principal energy levels, sublevels, and orbitals. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model Principal energy levels (shells): Roughly correlate to the distance that an electron is from an atoms nucleus. Sublevels (subshells): Each principal energy level (n) is divided into n sublevels. Orbitals: Orbitals are regions in space that represent a high probability of locating an electron. Each sublevel has one or more orbitals. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model Electron configurations: Allow us to represent the arrangement of the electrons in an atom. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model The order-of-filling chart: Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Arrangement: The Quantum Model Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Configurations and the Periodic Table The periodic table is considered by many to be the most predictive tool in all of chemistry. It is composed of vertical columns called groups (or families) and horizontal rows called periods. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Configurations and the Periodic Table Groups (families): Vertical columns in the periodic table. Groups contain elements with similar chemical properties. Periods: Horizontal rows in the periodic table. Elements in a period demonstrate a range of properties from metallic (on the left) to nonmetallic (on the right). Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Configurations and the Periodic Table Valence electrons: Valence electrons are the electrons in the outermost principal energy level of an atom. These are the electrons that are gained, lost, or shared in a chemical reaction. Elements in a group or family have the same number of valence electrons. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Configurations and the Periodic Table Some groups in the periodic table have special names: Alkali Metals: Group 1A Valence electron configuration: ns 1 Alkaline Earth Metals: Group 2A Valence electron configuration: ns 2 Halogens:Group 7A Valence electron configuration: ns 2 np 5 Noble Gases: Group 8A Valence electron configuration: ns 2 np 6 Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Configurations and the Periodic Table Metals, Nonmetals, and Metalloids: Metals Metallic luster, conduct heat and electricity, malleable, and ductile. Examples are sodium and copper. Nonmetals Dull luster, nonconductors, and brittle in the solid state. Examples are sulfur and bromine. Metalloids Demonstrate properties of both metals and nonmetals. Examples are silicon and arsenic. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Electron Configurations and the Periodic Table Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Green Chemistry Solar Fuels Sunlight is an abundant source of energy. Plants store solar energy as chemical energy via photosynthesis. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Green Chemistry Solar Fuels Artificial photosynthesis can be used to generate hydrogen fuel. Instructors Resource Materials (Download only) for Chemistry for Changing Times, 14/e John W. Hill, Terry W. McCreary 2016 Pearson Education, Inc. Green Chemistry Solar Fuels Hydrogen fuel can then be reacted with oxygen to produce heat and electricity.