Transcript for:
Understanding Atoms and Matter

🧪 Chemistry C165 Integrated Physical Sciences Section 2 Chemistry Section 2: Lesson 1 - Structure of Atoms Matter: anything that takes up space and has mass, composed of small particles called atoms Mass: a measure of how much matter it has (that is, how much "stuff" is in it). Not the same as weight. The international standard (SI) unit for mass is kilograms (kg). Atom: is the basic building block of matter. small particles that make up all matter, so small they can’t be seen under a microscope. Nucleus: the center of an atom where the protons and neutrons are located Protons: a positively charged subatomic particle; one of the two particles that make up an atomic nucleus Neutrons: a neutral (not charged) subatomic particle; one of the two particles that make up an atomic nucleus Electrons: Electrons, with their negative charge, are found outside of the nucleus, in zones that are called shells. Electrons have very little mass compared to protons and neutrons. They do not contribute to the overall mass of the atom. Electron clouds a diffuse region of negative charge surrounding an atomic nucleus; it describes the region in which electrons are located (their exact location is uncertain) Valence electrons: electrons that occupy the outermost regions, those farthest from the nucleus of an atom Charge Location Relative Mass Proton Positive +1 Nucleus/Center Contributes Neutron Neutral 0 Nucleus/Center Contributes Electron Negative -1 Outer rings, Electron Cloud Does NOT Contribute * Explain the importance of valence electrons. * These electrons are significant because they are part of the atom involved in chemical bonding and chemical reactions. When one atom interacts with another atom, it is the valence electrons that are involved. * Describe the connection between the identity of an atom and its atomic number (number of protons). * The atomic number of an atom is directly connected to the number of protons. If you change the protons, you change the atomic number. * Explain in terms of number of protons why bond formation does not change the identity of atoms. * Electrons are either shared or transferred between one or more atoms to make new substances in a chemical reaction. Only the outermost (valence) electrons are involved in this process. Atomic Number Row or Period Group or Column or Family Color-Coding Scheme The number of protons in an atom Metal, Metalliods, or Nonmetals ________________ Section 2: Lesson 2 - Elements, Compounds, and Mixtures Element: Compound: Organic compound: Inorganic compound: Chemical bond: Molecule: Pure Substance: Mixture: Homogeneous mixture: Heterogeneous mixture: Atomic Element Molecular Element Ionic Compound Molecular Compound Description Example Molecular Element Properties in common Molecular Compound Homogeneous Mixture Properties in common Heterogeneous Mixture ________________ Section 2: Lesson 3 - Solids, Liquids, and Gases Solid: Liquid: Gas: Macroscopic properties: Microscopic properties: Solid Liquid Gas Physical Characteristics Structure Motion or Energy Is it compressible? 🌎 Earth Science