Chapter 1 Lesson 3: Periodic Table of Elements PDF

# Day 1: Periodic Table ## Vocabulary * **Proton:** A particle with a positive charge in an atom's nucleus * **Neutron:** An uncharged particle in the nucleus of an atom * **Electron:** A negatively charged particle outside the nucleus of an atom ## Periodic Table Chapter 1: Elements: Building b...

# Day 1: Periodic Table ## Vocabulary * **Proton:** A particle with a positive charge in an atom's nucleus * **Neutron:** An uncharged particle in the nucleus of an atom * **Electron:** A negatively charged particle outside the nucleus of an atom ## Periodic Table Chapter 1: Elements: Building blocks of the Universe Ms. Joselyn ## What is Phlogiston Theory? * A 17th-century scientific theory to explain the process of combustion and oxidation. * Developed by J. J Becher. * A diagram depicts a piece of wood releasing phlogiston into the air as it burns. * The wood is labeled "Phlogiston Rich". * The ashes are labeled "No Phlogiston". ## Phlogiston Theory * Four elements: earth, air, fire, and water. * One early theory was that sulfur was the ingredient that caused combustion. * All matter contained a fatty substance that gives it definition. * Becher and Stahl called it a mysterious, unknown substance "phlogiston". ## Phlogiston * A diagram shows an example of the smelting of ores. * Fire gives phlogiston to earth ore to produce metal. * A diagram shows an example of the corrosion of metal. * Metal surrenders phlogiston to air to produce earth (calx). * A diagram shows an example of the combustion of wood. * Wood surrenders phlogiston to air to produce earth (ash). ## Gases have mass. * Gases seem to be weightless, but they are classified as matter, which means they have mass. * The density of a gas — the mass per unit volume — is much less than the density of a liquid or solid, however. ## Parts of an Atom * A diagram shows a proton, a neutron, and an electron in the structure of an atom. * **Proton:** Positive electrical charge * **Neutron:** Neutral * **Electron:** Negative electrical charge ## Vocabulary ### Atomic Number (Z) * The atomic number of an element is equal to the number of protons present in the nucleus of its atom. * Example: The atomic number of Hydrogen is Z-1. ### Electronegativity * The ability of an atom to attract electrons when bonded. * Nonmetals have high electronegativity. * Metals have low electronegativity. * Electronegativity increases across a period and decreases down a group. * A periodic table shows the electronegativity values for the elements. ## Why are noble gases unreactive? * The valence shells of noble gases are shown. * Each noble gas has a fully filled valence shell. ## Noble Gases Have Fully-Filled Valence Shells * A diagram shows the configuration of the electron shells of the noble gases. * Each noble gas atom is shown with a full outer shell of electrons. * Therefore, they don't need to react to become stable. ## Vocabulary ### Isotopes * An atom of the same element with a different number of neutrons. * A diagram depicts three examples of isotopes. * Protium (H): 1 proton and 0 neutrons * Deuterium (H): 1 proton and 1 neutron * Tritium (H): 1 proton and 2 neutrons ## Rutherford's Atomic Model * A diagram depicts Rutherford's atomic model: a positive nucleus surrounded by a cloud of electrons. * Atom has a positively charged central part (nucleus). * Electrons are distributed around the nucleus. * The mass of an atom is concentrated at the nucleus. * Compared with the total volume of an atom, the volume of the nucleus is meager. ## J.j. Thomson Atomic Model * Also known as the Plum Pudding Model or Blueberry Muffin Model. * Proposed in 1904. * Negatively charged electrons (raisins or blueberries) are surrounded by a positively charged “pudding” (or muffin). ## What are Isotopes? * Isotopes are atoms of the same element that have the same number of protons, but different numbers of neutrons. * This results in different atomic mass. * A diagram depicts the configuration of the isotopes of Hydrogen, Helium, and Lithium, all showing an equal number of protons with a varied number of neutrons. ## Definition of Isotope * Same atomic number (i.e., same number of protons), but different numbers of neutrons. * Carbon - 12 (12C): 6 protons and 6 neutrons * Carbon -13 (13C): 6 protons and 7 neutrons * Carbon -14 (14C): 6 protons and 8 neutrons (radioactive) * Isotopes of an element have the same chemical properties, except mass-dependent reaction rates.