physics module 2 gizmo cards

• Matter

  The material that makes up the universe - everything that takes up space and has mass
• Atom


  The simplest forms of matter, consisting of smaller particles called protons, neutrons and electrons
• Atom


  • Protons and neutrons make up the nucleus
  • Electrons move around the nucleus in layers, forming an electron cloud
• Fundamental forces in an atom

  • Electromagnetic force
  • Strong force
  • Weak force
• Protons

  Positively charged particles in the nucleus
• Neutrons

  Particles in the nucleus with no electrical charge, help produce the strong force
• Electrons

  Negatively charged particles that spin around the nucleus
• Atoms have over 99% empty space despite being solid objects
• Chemical element

  Substance that cannot be broken down into simpler substances by ordinary chemical processes
• There are 118 known chemical elements
• Periodic Table

  Presents the 118 known chemical elements

  
• An atom is the smallest part of an element that retains the properties of that element
• Electron shells/orbits


  Regions or layers where electrons are found around the nucleus

  
• Maximum number of electrons in each shell = 2n^2, where n is the shell number

  
• Carbon has an atomic number of 6, meaning it has 6 protons and 6 electrons in a neutral state
• Electron shells


  The basic regions or layers where you find electrons

  
• Shell numbering


  1 being closest to the nucleus, 2 the next closest, up to Q being the farthest away
• Maximum number of electrons in each shell

  2n^2, where n is the shell number

  
• The third electron shell (n=3) would have 2 x 3^2 = 18 electrons

  
• Building atomic models


  1. Determine atomic number

  2. Calculate number of electrons in each shell

  3. Ensure outer shell has max 8 electrons

  
• Atomic number


  The number of protons in the nucleus
• Mass number


  The sum of protons and neutrons in the nucleus
• The number of electrons equals the number of protons, making the atom electrically neutral
• Electron shells


  • First shell holds 2 electrons, next shell holds up to 8 electrons, subsequent shells can hold more

  
• Valence shell


  The outermost shell, its electrons play an important role in electrical conductivity and bonding

  
• An element with a full outer shell (8 electrons) is chemically inert and an electrical insulator
• Periodic table


  Elements are placed in order based on atomic number, position provides information about electron arrangement

  
• Atomic number


  Represents the number of protons in a single atom
• Chemical symbol


  An abbreviation of the element's name
• Relative atomic mass


  The average mass of the atoms of an element
• Relative atomic mass of copper is not a whole number because it is an average of two copper isotopes
• Isotopes


  Atoms of the same element with different mass numbers due to different numbers of neutrons
• Chemical bond


  The force that holds atoms together in molecules
• Covalent bond


  • Involves sharing of electrons between atoms to fill their outer shells
  • Forms a new orbit extending around both nuclei
• Ionic bond

  • One atom gives up valence electrons to another, forming positive and negative ions that are attracted
• Cation


  Positively charged ion formed when an atom loses electrons
• Anion

  Negatively charged ion formed when an atom gains electrons
• The number of protons in an atom is much more stable than the number of electrons
• Molecule


  Any bonded combination of atoms
• Compound


  A molecule comprised of multiple different atoms in a fixed ratio