PPT-4.4 Atomic Number and Mass Number

All atoms of an element have the same number of protons and the same atomic number Learning Goal Given the atomic number and the mass number of an atom state the number of protons neutrons and electrons. THINK ABOUT IT – answer on your warm-up sheet or scratch paper. W. hat are the 3 main groups on the periodic table?. What are the 3 main parts of an atom?. You need to get . 3. different . color pencils. The Periodic Table gives us SO much information about the world around us, but first you have to know how to read it!. Each of these little squares tells us about one specific element.. Reminder!: An Element is a pure substance made of all the same type of atom!. #1: Rubidium has two common isotopes, . 85. Rb and . 87. Rb. . If the abundance of . 85. Rb is 72.2% and the abundance of . 87. Rb is 27.8%, what is the average atomic mass of rubidium?. PROCEDURE:. Electron. -. ve. charged particle. Outside of nucleus. Thomson’s discovery. Mass = 9.11 x 10. -28. g. Charge = -1.76 x 10. 8. C (coulombs). Proton. +. ve. charged particle. Inside nucleus. Rutherford’s discovery. Chemistry. Learning Goals . To be able to . explain and draw atomic structure. Elements. Elements are the . building blocks. of all . matter. on Earth. Elements are made up of . atoms. Differences in . Chapter 1D. Warm Up November . 28. What is smaller, an atom or a cell? . Name and describe one element that you are familiar with on the periodic table. . When large blooms of algae die, decomposers use all the oxygen in the water to break down the dead algae. What is this a result of? . I. Foundations of the Atomic Theory. A. 400 B.C. –Democritus. 1. Defined nature’s basic particles as . atoms. a. means indivisible. B. 350 B.C. Aristotle. 1. said matter was made of the 4 “elements”. Chapter 3. Types of Models – Why do we use models?. Physical Model vs. Conceptual Model. Physical model. is a representation of a very large or small object shown at a convenient scale. . Steps for Calculating Average Atomic Mass. (. When given percentages of each isotope and each isotopes mass). 1. Convert the percentages into decimals. (This percentage is known as . its . relative . #1: Rubidium has two common isotopes, . 85. Rb and . 87. Rb. . If the abundance of . 85. Rb is 72.2% and the abundance of . 87. Rb is 27.8%, what is the average atomic mass of rubidium?. PROCEDURE:. Atomic mass. Atoms of different elements have different masses. . Mass of a single atom is incredibly small so a special unit called atomic mass unit (. amu. ) is used. . Atomic Mass. Atoms are composed of three particles:. III. How atoms differ. . A. Atomic Number. Equal to the number of protons – never changes; equals the number of electrons if AND ONLY IF the atom is . neutral. ; Moseley discovered . each atom has a unique number of protons in the nucleus. Atoms are the basic units of all matter.. Protons . (+) . Neutrons . (0. ). Electrons (-). Atoms are composed of 3 sub-atomic particles:. . An atom is the smallest particle of an element.. Elements. Elements, Mixtures and Compounds. Atoms and molecules. Remember that an . element . is one type of atom, like carbon, gold or chlorine. We will look at three ways that atoms can exist.. 1. Single atoms.