Chapter 5 Glossary Terms

  1. Atom Definition
    the smallest particle of an element that retains the identity of the element
  2. Electron Definition
    a negatively charged particle within the atom
  3. Subatomic Particle Definition
    a particle that is smaller than the atom
  4. Nucleus Definition
    the positively charged centre of an atom
  5. Proton Definition
    a positively charged particle that is part of every atomic nucleus
  6. Neutron Definition
    an uncharged particle that is part of almost every atomic nucleus
  7. Energy Levels Definition
    a possible level of energy an electron can have in an atom
  8. Atomic Number Definition
    the number of protons in the nucleus of an atom
  9. Mass Number Definition
    the sum of the number of protons and neutrons in the nucleus
  10. Isotope Definition
    one of two or more forms of an element that have the same number of protons but a different number of neutrons
  11. Bohr-Rutherford diagram Definition
    a model of the atom in which a central positive nucleus is surrounded by electrons in energy levels
  12. Atomic mass Definition
    the average mass of the naturally occurring isotopes of an element
  13. Periodic Table Definition
    a system for organizing the elements into columns and rows, so that elements with similar properties so they are in the same column
  14. Metal Definition
    typically, an element that is hard,shiny, malleable, and ductile and is a good conductor of heat and electricity
  15. Non-metal Definition
    typically, an element that is not shiny, malleable, or ductile and is a poor conductor of heat and electricity
  16. Metalloids Definition
    an element that shares some properties with metals and some with non-metals.
  17. Period Definition
    a horizontal row of elements in the periodic table
  18. Group Definition
    a vertical column of elements in the periodic table
  19. Alkali Metal Definition
    Elements that are very reactive, electropositive, monovalent metals
  20. Alkaline earth metal Definition
    elements that are reactive, electropositive, divalent metals
  21. Halogens Definition
    elements that are reactive nonmetallic elements
  22. Noble Gases Definition
    gaseous elements that are hardly reactive with other elements; these gaseous elements are located in group 18
  23. Valence electron Definition
    an electron in the outermost occupied energy level of an atom
Card Set
Chapter 5 Glossary Terms
Chapter 5 Glossary Terms