Science Q2

• Atoms


  The building blocks of matter that make everything that we encounter everyday
• Parts of an atom

  • Proton (+)
  • Electron (-)
  • Neutron
• Ernest Rutherford


  • First theorist of atom
• Neil Bohr


  • Slightly modified Ernest's theory
• Electrons are stable, like how the planets in our solar system don't move and have their own orbits
• Any charged object which revolves in a circular motion gains acceleration
• Ways to name energy levels

  • Using letters (capital)
  • Using numbers (w/n)
• Atomic Models

  • Solid Sphere Model
  • Plum Pudding Model
  • Nuclear Model
  • Planetary Model
  • Quantum Model
  • Wave Mechanical Model
  • Quantum Mechanical Model
• Solid Sphere Model


  • Made by John Dalton during 1803, able to explain the law of conservation of mass
• Plum Pudding Model

  • Made by J.J. Thomson by 1964, an atom possesses a spherical shape in which the positive charge is uniformly distributed
• Nuclear Model


  • By Ernest Rutherford, a particle scattering experiment
• Planetary Model


  • By Neil Bohr, "he worked on the dual character of electromagnetic radiation"
• Quantum Model


  • Using wave functions, proposed by Erwin Schrodinger
• Wave Mechanical Model


  • Proposed that the electrons act like particles as well as waves of energy
• Quantum Mechanical Model


  • Refers to the new model for the hydrogen atoms which may be applicable to other atoms, formulated by Werner Heisenberg's uncertainty principle
• Ground State


  Lowest energy level or energy state that an electron normally occupies
• Excited State


  Highest energy state farther from nucleus
• Atomic Orbitals

  • S orbital (spherical cloud)
  • P orbital (dumbbell shaped cloud)
  • D orbital (four leaf clover)
  • F orbital (complex appearance)
• Orbitals illustrated as electron clouds
• Ionic Bond


  Transfer of electrons from one atom to another
• Stability (Octet Rule)


  8 electrons in an element, compound is two or more atoms
• Ionic Charges

  • Cation (positive charge, loses electron)
  • Anion (negative charge, gains electron)